London Loop 13/14: Harefield - Moor Park - Hatch End

Englishmen's castles: Moor Park estate.

THE LONDON LOOP NOW CLIMBS OUT OF THE COLNE VALLEY and through the rolling fields of Hertfordshire on its most genuinely rural stretch since passing through Farleigh in Surrey in section 4. It runs through three substantial public woodlands (Park Wood, Bishops Wood, Oxhey Woods), across a fragment of heath and through the exclusive 1920s garden village of Moor Park. The trail then returns to London through the soggy fields of a stud farm and past an ancient farmhouse to finish at suburban Hatch End.

Another double helping of Loop sections, this walk is best split if required at the official break point of Moor Park Tube. There are a few other bus options, but some of these are outside the Transport for London (TfL) zone so Travelcards, Oyster and contactless might not be valid.

Old Park Wood

Both the Loop and the Hillingdon Trail climb away from the Colne along an old lane that’s now a rather tucked away residential street, Summerhouse Lane. From here there’s a good view of redeveloped Royal Quay, on the site of the old Harefield mill, and one last glimpse of the Grand Union Canal and the river at Coppermill Lock. Look at the map and you’ll see that further north, the valley curves eastwards, forming a corner, with the promontory of high ground you’re now ascending to its southeast.

Then the path itself turns east, through Old Park Wood. This ancient woodland with hazel coppices, mentioned in the Domesday Survey, was once part of Harefield Park, centred on the mansion that’s now the site of Harefield Hospital. It’s a Site of Special Scientific Interest managed as a nature reserve by Herts and Middlesex Wildlife Trust, particularly prized for its bluebells and other spring flowers including celandine and yellow archangel. To the south, off the route, is a pond with an observation platform, noted for dragonflies and damselflies. According to the Trust, it’s one of the most diverse nature sites in former Middlesex.

Hill End, where the path emerges onto the road again past allotments, may be named after a person rather than its geography. This outlying hamlet of Harefield, strung out along a country lane, is a relatively recent development, built largely in the second half of the 19th century as accommodation for workers in the nearby brickfields and quarries. The Hillingdon Trail diverges again here, heading northwest to end on the canalside again at Springwell Lock. If you want to go this way, and perhaps end up in Rickmansworth, you'll find more on my Hillingdon Trail page. But the official Loop route is across the fields of Cripps House Farm, transforming briefly into a classic English lowland ramble alongside hedgerows and across stiles. Nowadays, of course, there’s little genuine agriculture going on – the farm, and the next one along, are both equestrian centres.

Into Hertfordshire

Looking into Hertfordshire at Fieldways Farm

The trail dips into a small valley to bridge a minor tributary stream of the Colne then climbs again across a substantial hedgerow that marks the boundary of London, and former Middlesex, with Hertfordshire. The county as a distinct area dates back to 9th century Saxon England when it was split between the kingdoms of Mercia and Essex. Hertford, the county town, some way to the east, was already a significant place when a church synod decided on how to calculate the date of Easter there in 673, and later became a fortified borough.

The county was consolidated within something like its present boundaries in the 970s. Several main roads from London run north through it and its fate has been tied to the development of the capital – with generally rich soils, it was an important source of grain for Londoners, and in the 19th century parts of it became intensively industrialised, particularly noted for brewing and papermaking and, more recently, for pharmaceuticals. Hertfordshire is still a shire county with a two-tier system, subdivided into districts, and the one we now enter is Three Rivers, created in 1974 and referencing the Colne and its tributaries the Chess and the Gade in its name.

The Rose and Crown at Woodcock Hill

The first Hertfordshire buildings the Loop passes house another equestrian enterprise, though with a difference. As previously noted at Denham, this stretch of the London fringe is particularly noted for its association with the film industry, and R&S Dent at Fieldways Farm, established in 1945, specialises in supplying horses and carriages for film and TV work. The horses, boasts the website, “range through stunning Spanish stallions that perform all stunt work, striking carriage horses, strong work-type horses and right down to donkeys and mules.” Over 200 period horse-drawn vehicles are also on offer, and the company has contributed to productions including Casino Royale, Gladiator and Les Misérables.

A permissive path behind the houses, avoiding the need to walk along Harefield Road, takes you to a pretty but rather isolated pub, the Rose and Crown on Woodcock Hill, which, unexpectedly, is still open (at least when I visited). The core of this is a modest two-storey timber-framed 17th century building which qualifies it for a Grade II listing, although like most pubs it’s been much altered and extended. The bus stops nearby are outside the warm embrace of Transport for London, as you might realise when you check the timetable to find there isn’t even a daily service.

Crossing the road at Woodcock Hill, the Loop finally leaves the Colne Valley Regional Park, although there's plenty of attractive countryside still ahead.

Bishops Wood

Bishops Wood Country Park

After another couple of fields, the trail grazes the edge of Long Spring Wood, a smallish 4 ha fragment of semi-natural ancient woodland with sweet chestnut coppices, birch, cherry and field maple trees, roamed by muntjac deer. It’s managed by Three Rivers council, and separated from a much bigger 38.4 ha area of council-owned woodland by a strip of open grass. The Loop now plunges through this, into the valley of a stream that rises at the ‘long spring’ of the previous wood.

This is Bishops Wood Country Park, a site the council bought in 1960, and initially started replanting with fast-growing conifers, as was the fashion of the time. Such trees form a much thicker canopy than the native broadleaved oak, ash and hazel that have grown on the site for centuries, reducing biodiversity. The wood later fell into neglect, but in 2014 a restoration project began with the help of a Forestry Commission grant. Most of the conifers are being progressively removed, clearings and fragments of heathland opened up, and coppicing resumed. Loop walkers are already benefitting from this work as paths and cycleways through the site were significantly improved in 2014.

There are several sections of the wood known by different names. To the north, where the Loop first enters, is Park Wood; the area around the main junction in the middle of the wood is Poorfield; while the eastern strip is Lockwell Wood. The path continues through a separate but adjoining woodland known as White Hill and emerges on the open grass of Batchworth Heath.

Batchworth Heath

Pond and cottages at Batchworth Heath

Batchworth is part of the former common land of the ancient Manor of the More. From pre-Norman times until the Dissolution this was itself part of a larger stretch of land in and around the valley that ultimately fell under the authority of St Albans Abbey, though was at various times leased to others. It’s said King Offa granted the land to the monks in 780, which is likely why, despite being south of the natural boundary of the river Colne, this area has always been part of Hertfordshire rather than Middlesex. The high ground above the river, formed of glacial sands and gravels, was likely used for rough pasture since at least Offa’s day. The combination of intense grazing and rather poor soils resulted in its current appearance, with its distinctive heath-like vegetation.

Sometime in the mid-18th century the heath gained a new function as a traveller’s rest when the Pinner turnpike, now the A404, opened across it from Harrow and Pinner to Rickmansworth, forming part of a route from Amersham to London. The road, which most likely followed an earlier ancient trackway, had an important junction here with lanes to Harefield and Oxhey.

The Green Man pub, which dates back to the late 16th or early 17th century, now became a coaching inn and the surrounding heathland grazing for resting horses. By this stage the heath was already reduced in extent, and the transport links encouraged housing development, but thankfully the sprawl of London hadn’t quite reached this far by the time development controls were introduced towards the mid-20th century. The remaining open areas are now protected Green Belt and the locality is also a Conservation Area, reflecting the way in which the particular configuration of historic buildings, green space and highway gives the place a particular, and very varied, character.

Just to your left soon after you emerge on the open grass, look out for a pond and, beyond it, a quaint red brick cottage and a roof like an oversized comedy hat. The cottage is one of the oldest on the heath, dating back to the 17th century though with numerous later alterations. The pond, which would once have watered horses and cattle, is now much smaller than it was even as late as the 1930s, but still provides a pleasant visual focus. A little further along, across the green to your left, is a fine 18th century red brick mansion, Batchworth Heath House.

Ahead, on the other side of the turnpike, in its own generous plot, stands the pub. The current faux-archaic form of its name, Ye Olde Greene Manne, was doubtless the affectation of a brewery marketing department, perhaps when it was refurbished in the 1930s. But parts of the buildings are genuinely old: one bay of the original late 16th or early 17th century timber-framed hall building survives, with extensions from the first half of the 18th century.

The Loop follows the turnpike briefly east, passing a bus stop reassuringly bearing a TfL roundel even though it’s just outside the London boundary. Soon, across the heath to your left, is a massive Portland stone entrance gate supported by Doric columns, with flanking lodges, built in 1765 by Robert Adam as the grand entrance to the manorial park. Then the road swings south towards London, passing the Prince of Wales, a rather more modest pub though with a handsome flint façade, dating from the 1860s. If you look carefully, the building appears to be part-missing: half was felled by a V1 flying bomb that fell on the heath in 1944.

Coal post at Batchworth Heath where Hertfordshire and
London still meet today, as road surface seam indicates.

A little south of this, the second coal post on the Loop stands by the roadside, marking what was then the edge of Middlesex and the Metropolitan Police District and is now, as the Hillingdon sign nearby confirms, the edge of Greater London. There’s more about these curious markers in the previous section. But the southern edge of the heath formed the boundary of Hertfordshire long before the post was installed in the 1860s, and the trail now turns east again to follow an ancient footpath along this divide, which now finds its way through a strip of overgrown heathland behind encroaching houses. Further on, just off the path to the left and half-hidden in a clump of bushes, is another coal post.

Emerging on Kewferry Road, a very brief detour of a few paces right into Northwood in the borough of Hillingdon takes you to the corner of Ebury Road. The detached house at no 55 might look familiar to fans of classic British sitcoms. Between 1975-78 it was used as the main exterior location for The Good Life, starring Richard Briers and Felicity Kendal as middle class suburbanites trying to become self-sufficient, and Penelope Keith and Paul Eddington as their snobby neighbours.

Every year during the series run, according to the Daily Telegraph in a piece written when the house went on the market in 2001, the BBC “arrived with pitchforks and Rotovaters to dig up the garden, erect pig pens and chicken runs and cause general chaos,” re-landscaping once filming had wrapped. “The goats and chickens would be standing in the road when you got up,” recalled a neighbour. “It was all rather fun.”

The Manor of the More

The ‘more’ after which the manor is named doesn’t refer to a ‘moor’ in the modern sense but is from the Old English mor meaning marshland, the ancestor of the word ‘mere’: the area was well-watered by tributary streams of the Colne draining from the high plateau. There’s evidence of human habitation going back at least to the Bronze Age here, and the remains of a Roman villa dating from around 130 CE now lie under Moor Park golf course, to the north of the heath.

The manor was occupied by numerous powerful figures over the centuries, including monarchs Edward IV and Richard III, and George Neville (1432-76), Archbishop of York and Chancellor of England. By 1520 it was back with St Albans Abbey, and so came into the hands of Thomas Wolsey (1473-1530), the influential advisor to Henry VIII, who was made abbot that year. As we’ve already discovered at Bushy Park near Hampton Court Palace, Wolsey was a keen palace builder: he extended the manor house along the model of Herstmonceux Castle in Sussex. Henry himself briefly occupied it following Wolsey’s fall, and gave it to Anne of Cleves on their divorce. But following long periods of neglect in the later Tudor period, the house was demolished for safety reasons in 1661.

The site of the house, now a Scheduled Ancient Monument, lies some way to the north of the Loop, under the playing fields of Northwood Preparatory School. It’s been excavated twice, once in 1952-55 for a project instigated by the neighbouring Merchant Taylors independent school, and again in 2012 for Channel 4’s Time Team programme, with the assistance of the prep school students. Both found extensive evidence of the various buildings on the site, and the 2012 dig found further remains of Wolsey’s palace, though some of the features mentioned in contemporary accounts couldn’t be identified.

The estate was broken up in 1630, with the deer park to the southwest sold as a separate property. A new mansion had been built on higher ground there sometime in the 1620s, and this was subsequently rebuilt twice, first in 1678 for James Scott, Duke of Monmouth, and again in Palladian style in 1720.

Both parts of the estate eventually passed into the hands of the Grosvenor family. Robert Grosvenor, 1st Baron Ebury (1801-93), was a Whig politician, homeopathy advocate and railway speculator who in 1862 worked with the Great Western Railway (GWR) to open the 7.2 km Watford and Rickmansworth Railway (W&RR) connecting the two towns, with the intention of extending it to the GWR’s line at Uxbridge. The line wasn’t a success and was left incomplete – it finally closed in 1960, and is now largely a walking and cycling trail called the Ebury Way which we’ll explore at a later date. But it did indirectly inspire the Metropolitan Railway to extend to the area.

Under the Metropolitan Line at Moor Park

The Metropolitan was of course the founding father of the London Underground, opening what’s now the stretch of the Circle, Hammersmith & City and Metropolitan Line between Paddington and Farringdon in 1863. The Met’s original aim to link main line terminals didn’t yield enough customers, so it began to extend into other parts of London and suburbia, and eventually developed the ambition to become a main line on its own account. In 1880 it opened to Harrow on the Hill, then a separate town still clearly distinct from London.

Meanwhile, in 1868 the Aylesbury and Buckingham Railway (A&BR) opened its line from Aylesbury to Verney Junction in Buckinghamshire, with long and convoluted connections to Oxford and London via the Great Western. The A&BR originally got permission to create a London link from Aylesbury to Rickmansworth and then to Euston via Watford, but in 1875 it agreed with the Met to continue south to Harrow, and the line straight through the Manor of the More opened in 1887. The Met eventually took over the A&BR completely, but it never did complete its main line before it was nationalised along with the rest of the London Underground in 1933.

In 1908, a keen golfer and former mining engineer called James Markes persuaded the second Lord Ebury to lease the northeast part of the estate around Sandy Lodge Farm as a golf course, taking advantage of deposits of sand which lay just below the surface. Opened in 1910, the course was promoted for its supposed seaside character, easily accessed from London via the new Sandy Lodge Halt on the Met.

When Ebury died in 1919, the estate was sold to the Bolton-born soap magnate William Lever, Viscount Leverhulme (1851-1925), co-founder of Lever Brothers, now the multinational Unilever. He also saw it as a golfing destination, creating two further courses from the land to the west of the railway line, now Moor Park Golf Club, with the mansion as the clubhouse, a function it still serves today. During World War II the house was commandeered as a headquarters of the British Army’s 1st Airborne Division, and was used to plan Operation Market Garden, the disastrous Allied attempt to push across the river Rhine in 1944.

Today Moor Park is probably best known as an exclusive, upmarket housing estate, and it’s this part of the old manor through which the Loop now turns, past neat white gates and along grassy verges lined with fine mature trees. Massive detached houses set back from the streets on generous plots are largely in the typical Tudorbethan style of the 1920s-30s, with fake half-timbering, half-hipped roofs, mullioned windows and prominent fancy red brick chimneys. Amid all this stands an electricity pylon, fenced off in its own little square utilitarian ghetto.

It’s one of the most fully-formed domestic expressions of the architecture that arose from the suburban expansion of the early 20th century, when London’s middle classes, and even its better-off skilled working classes, were encouraged to become commuting property owners, grabbing their own patch of a promised rural idyll on the urban fringe.

It’s no accident that the style nostalgically recalls an England of pre-industrial times, just as the pace of social change, urbanisation, industrial expansion and mobility accelerated to unprecedented levels, and the spread of suburbia engulfed much of London’s countryside. The Good Life, in its gentle BBC way, poked fun at the same ideology, as its protagonists took suburbia’s promise at its word by attempting to create a rural idyll in their own Englishman’s castle, only to find out that their neighbours didn’t quite share the same conception.

Section 13 of the London Loop ends at this
fingerpost in the corner of Sandy Lodge golf course.

Because of its proximity to the Metropolitan Line, the Moor Park estate is often cited as the most exclusive corner of Metro-Land, the brand coined for the mass of new suburbs developed by the railway company on its surplus lands during the same period. John Betjeman even included a sequence of him playing inept golf on Moor Park course in his classic 1973 documentary Metro-Land.

But this isn’t strictly speaking correct. Although the Met helped facilitate the development by expanding the golf club halt into a fully-fledged station, which was renamed Moor Park and Sandy Lodge, the initiative was Lever’s. He transferred 117 ha of land to a subsidiary of Lever Brothers, Moor Park Ltd, which began work in 1922. Building was interrupted by the war, but continued between 1954-58: some houses in modernist style date from this period. Today the site, which was designated a Conservation Area in 1995, is managed jointly by the residents, through a successor company, Moor Park (1958) Ltd, which has no connection to Unilever. And if Moor Park was exclusive then, it’s even more so now: some of those five-bedroom Tudorbethan castles currently top £3 million.

Section 13 of the Loop ends at the corner of a rough meadow in the southwest extremity of Sandy Lodge golf course, only a short walk south of the station. This has been known simply as Moor Park since 1950, a name change which apparently infuriated the golf club committee of the day. The current station is the result of a 1959 rebuilding but still has echoes of a rural halt. If you continue on the route at this point, you’ll find yourself heading northeast across the golf course itself, though I doubt you’ll feel you’re on a seaside links these days.

South Oxhey

Pond in Oxhey Woods

At Sandy Lane, the Loop leaves the old Manor of the More and enters what was once the next manor, Oxhey, from Oxangehaege, ‘fenced enclosure for oxen’. This was also part of the land supposedly gifted to St Albans Abbey by Offa, but has a separate history. For much of the early mediaeval period it was worked as a ‘grange’ supplying the abbey – it’s said the monks built the first bridge over the Colne in Watford to transport the estate’s produce home more easily.

The manor was later subdivided and passed through several hands, but remained an almost completely rural area until very recently, with only a small settlement around the manor house towards the south. The first part to be developed was to the north, as essentially a suburb of Watford, in the second half of the 19th century, spurred by the opening of the railway in 1838 (of which more later). This portion is still known as Oxhey today. The southern portion, round the old manorial core, wasn’t developed until much later, and in a rather different way, as we shall shortly see.

Crossing the lane, you’re only just above the Colne, a short distance downhill to the left (north). The riverside here was the site of mediaeval Oxhey Mill, renamed Hamper Mill after the Dissolution. Most recently it operated as a paper mill, closing in 1908, and several historic buildings still stand, including a late 18th century clock tower. The woodland the Loop enters on the other side is still known as Hampermill Wood.

The wood forms part of a strip of council-owned Green Belt land known as South Oxhey Playing Fields, a name that really doesn’t do it justice, as besides formal sports fields there are notable areas of meadow, woodland and scrub in quite an attractive patchwork. Some of the woodland is ancient: Hampermill has oak, ash, wild cherry and coppiced hornbeam, with bluebells in season. Emerging from the wood, the view of the undulating site might give away its past history as yet another golf course, from 1912-52.

The high open prospect also reveals what happened to the rest of Oxhey manor in the second half of the 20th century: it was developed as a single vast housing estate, South Oxhey. The neatly laid-out streets of brick detached houses, densely concentrated but surrounded by swathes of grass and woodland, provide an interesting counterpoint to the luxury of Moor Park. And, even more so than Moor Park, its history is inextricably linked to London, as a Hertfordshire outpost of the London County Council (LCC).

In 1877, this land, by now known as Oxhey Place after the manor house, was bought by Thomas Blackwell (1804-79). In a classic Victorian rags-to-riches story, he began his career as a humble apprentice at food manufacturer West & Wyatt in Soho Square. In 1829 he took over the firm in partnership with another former apprentice, Edmund Crosse, renaming it Crosse & Blackwell. Blackwell’s descendants were effectively the last lords of the manor, selling their holdings to the LCC in 1944.

As explained several times previously, the LCC’s own territory was notably smaller than the current Greater London and certainly didn’t stretch out this far, but there was nothing to stop it buying and managing land anywhere as any private landowner would. State intervention in housing in London dates back to 1875 when the LCC’s forerunner the Metropolitan Board of Works began tackling some of the worst slums, and the LCC started building its own housing estates in 1890.

This activity ramped up after World War I in response to pressure to provide returning servicemen with ‘homes fit for heroes’, and was given further impetus in the period of rebuilding after the next war. Quite a few big LCC developments were on greenfield sites outside its own area, partly because land was more readily available, partly because of the belief that working class people would benefit just as the middle classes did by migrating from the inner city to greener, healthier environments further out.

Over 4,000 homes were built here between 1946 and 1953, swelling the population from a handful to a peak of 17,000. Curiously, when the capital’s boundaries were expanded in 1964, the boundary commissioners considered whether South Oxhey, which was only separated from the rest of the built-up area by the thinnest of buffers, should be absorbed, but concluded it “looked to Hertfordshire” rather than to London, despite its history. It remained part of what was then Watford Rural District, though the Greater London Council (GLC) inherited the housing.

With local government reorganisation outside London in 1974, the rural district was abolished and South Oxhey became part of the new Three Rivers district council area, separating it from Oxhey to the north, which was placed in Watford borough along lines surprisingly similar to the old manorial bounds. The civil parish retains the name Watford Rural, despite being neither rural nor part of Watford.

The GLC finally passed the housing on to Three Rivers in 1980, by which time many of the residents were exercising their ‘right to buy’, introduced that year. Today, South Oxhey is a model of the home-owning democracy foreseen by Margaret Thatcher, with around 70% of the houses privately owned, and the rest offloaded to a housing association, Thrive Homes. Meanwhile some of the locals are petitioning for the area to become part of London, saying they’d enjoy better public transport and lower council taxes if transferred to Hillingdon.

Primroses in Oxhey Woods

One delightful aspect of the original estate design was the preservation of extensive green space, including a magnificent 98 ha swathe of woodland, Oxhey Woods Local Nature Reserve, the third big public wood on today’s walk. Parts of this are known to date back to the last glacial period over 11,000 years ago. Proof of its patrimony is the presence of the rare wild service tree, an indicator of ancient woodland. The trees are punctuated by meadows and glades with scrub and gorse, which formerly would have been grazed. An active Conservation Volunteers group helps maintain the reserve.

The trail enters at an area known as Old Furze Field, where gorse once would have been grown as fodder. It almost leaves the woods soon after this near a bend in Gosforth Lane, one of the main streets through the estate. The old manorial centre and the current shopping and community centre are about a kilometre east along the lane.

The manor house, by then much rebuilt, burnt down in 1960, and the only historic building still standing is Oxhey Chapel, a modest knapped flint and red brick structure built as a private chapel for the house in 1612, probably on the site of a much earlier church that once would have been attached to St Albans Abbey. Close by is the modern All Saints Church and community centre, opened in 2000 to replace the first church built on the new estate in 1953, which had to be demolished as it contained dangerous quantities of asbestos.

The Loop crosses two roads that now divide the woods, then a stream, then a track known as Rhododendron Walk, an old route through the woods which was planted with rhododendrons as a decorative feature in the mid-19th century. Diverting west (right) here along the track will take you to the easy access sculpture trail, installed when the whole site was refurbished in the early 2000s. But the Loop continues south then east, through an area known as Nanscot Wood, leaving Oxhey and its woods to return to London.

Pinnerwood

Pinnerwood House

Unexpectedly, crossing back into London at the end of the woods, the Loop takes to paths around the edges of open fields, on one of the most rural-looking, and soggiest, stretches of today’s walk. You’re now in the London Borough of Harrow, and the boundary here follows the line of the old Harrow parish. This also has its origin in Offa’s land grants, but not this time to St Albans, which is partly why you’ve now left Hertfordshire and returned to historic Middlesex.

In mediaeval times, Harrow was a large and sprawling parish stretching from the Hertfordshire boundary here right down to the river Brent in the south, including places like Wembley which are now in the London Borough of Brent. It was a dispersed parish, with multiple small agricultural hamlets linked by paths and tracks, and a centre of sorts where the main church was, on top of the tall hill to the south where Harrow School now stands. It’s likely that a pre-Christian temple, or hearg in Old English, preceded the church, thus the place name. I’ll have more to say about this hill when I finally tackle the Capital Ring.

One of Harrow’s hamlets, in the high and gravelly northwest, was Pinner, with a name likely derived from the personal name of a local landowning family – the name of the river Pinn, the tributary of the Frays and Colne that runs close by, is probably a back-formation. Pinner was an important place in its own right by 1336 when it gained a weekly market and annual fair. This part of the area was once wooded and managed for hunting, an extension into Middlesex of Oxhey Woods, and even in the late 18th century much of it was still hilly and woody. The fields here were likely cleared by then, and attached as they still are to Pinnerwood Farm.

Look behind you as you leave the woods and walk through the fields and you'll see a big white mansion up on the hill. This is Pinner Hill House, built in the 1780s on the site of a house belonging to a former Lord Mayor of London and prominent member of the East India Company, Christopher Clitherow (1578-1641). Today it's yet another golf course clubhouse, though the surrounding greens do encompass fragments of ancient woodland.

The farm, inevitably, is now an equestrian business: as Pinnerwood Arabian Stud, it has bred show and racehorses since 1964. Be warned: wet weather, sticky London clay and churning hooves can turn the last stretch of field path towards the farmyard into a marsh. There’s an interesting group of buildings among the fields here, including a 19th century farmhouse and a cottage from 1867, but the most attractive is Pinnerwood House, which presents a picturesque scene from across a pond as you leave the farm along a track. This is a timber-framed building dating from around 1600, with a tall original chimney and some 17th century panelling inside. It was once rather bigger than it is today.

The trail finally runs along the backs of houses to a stile onto the street. Like a pinball from a flipper, the main route of the Loop bounces away from the built-up area here, northwards towards Hertfordshire again along another field edge. But to end your walk here, you’ll need to venture into the suburbia of Hatch End.

Hatch End

Hatch End station, a miniature masterpiece.

The station link follows a street called Grimsdyke Road, as roughly where one end of Hillview Road joins on the left, it crosses the line of the prehistoric linear earthwork known as Grim’s Dyke. As the next section of the Loop encounters a much more visible remnant of this, I’ll discuss it later. The street, lined with semi-detached houses, forms the eastern extremity of the large estate of Pinnerwood Park, developed in the 1930s for the Artizans [sic], Labourers and General Dwellings Company and originally intended for affordable rent to the skilled working classes on a ‘garden suburb’ model, though today the houses are almost all owner-occupied and rather less affordable. It’s now a conservation area.

Hatch End was originally a small hamlet on Headstone Lane just south of the Uxbridge road: its name suggests a gateway through a boundary, perhaps into the former deer park at Pinner Park. As development spread out from the nearby station, the name spread with it, and what most people now think of as the ‘centre’ of Hatch End is the 1950s commercial strip of the Broadway, some way west of the original hamlet and to your left as you emerge on Uxbridge Road.

The railway is actually one of the earliest in London, and the capital’s first intercity line, the London and Birmingham Railway. This stretch was first operational in 1837 when trains ran through without stopping on their way between London Euston and Boxmoor (now Hemel Hempstead), extending to Birmingham the following year. In 1846 the line became part of the London and North Western Railway (LNWR) and is now the southern section of the West Coast Main Line.

Initially, the railway focused on longer-distance traffic rather than commuting. The station at Hatch End, originally named Pinner, opened in 1844, but with few services calling, and even fewer that took third class passengers, it initially prompted the construction of only a few big houses for well-off people who didn’t have to be in the city every day. Large villas were built on Woodridings Farm (its name indicating a clearing in the wood) to the south of Uxbridge Road from 1855, and the area was developed more intensively from the 1880s as rail services improved and better water supplies were installed.

In 1897 the station was renamed Pinner and Hatch End to distinguish it from the Metropolitan Railway’s Pinner station closer to the village, then Hatch End (for Pinner) in 1920 and finally simply Hatch End in 1956. Connections to the Underground were improved in 1915 when the Bakerloo line was extended to Queens Park, further up the line towards Euston, and in 1922, a new pair of electrified tracks between Euston and Watford improved commuter services, some of them now direct Bakerloo Line trains. These days the Tube stops short at Harrow & Wealdstone, and local trains beyond are operated as part of TfL’s London Overground network.

The station building itself, a 1911 rebuild, surprises as arguably the most beautiful such structure on the trail. The main entrance is through a compact, near-square red brick building in a vaguely French-looking Romanesque style, festooned with white stone reliefs of roses, thistles and shamrocks symbolising the countries served by the LNWR. A slate roof is surmounted by a cupola and clock.

Michael McNay in Hidden Treasures of London suggests it may be “the prettiest station in England…a more expressive railway station than the Gothic monster in St Pancras”. It’s one of the few major works of Gerald Callcott Horsley (1862-1917), son of the watercolour artist John Callcott Horsley, and one of the artists who set up the Art Workers’ Guild in opposition to the Royal Academy. While I’m quite a fan of the aforementioned Gothic monster, I’d agree that with its modest elegance, this little gem of a building provides a fine conclusion to a fascinating walk.

• Download full route description (PDF)
• View Google map
• Official Transport for London pages:
  Harefield West to Moor Park
  Moor Park to Hatch End

London Loop 11/12: Hayes (Hillingdon) - Uxbridge - Harefield

Horton Bridge, Grand Union Canal

THIS WALK FIRST HEADS WEST, towards the Colne Valley Park, then north through the park along the valley itself, essentially following the Grand Union Canal. It’s one of the greenest and bluest sections of the London Loop, almost entirely off-road and largely beside water. It’s also arguably one of the least varied, although there are some diversions to provide a respite from towpath walking: through the odd blend of business centre and country park at Stockley, around some placid lakes set among woodland, and along the river Colne itself.

This is another concatenation of two official Loop sections, creating a relatively long walk, though as it’s along well-defined paths in flat country, you should make good time. The official break point is Uxbridge, particularly convenient as it’s on the Tube, but there are several other places with bus connections, including the end point which, rarely for the Loop, is at a bus stop rather than a station.

A short path between Stockley Park and Horton, now mentioned in the text below as an update, has made this section even more traffic-free. Another alternative option, which you might want to consider if rewalking the Loop or as a walk in its own right. The Hillingdon Trail leaves the Loop on the Grand Union Canal near Bulls Bridge and finds its own way along the Yeading Valley, rejoining the Loop at Harefield. It's rather a longer option, though, so might be best split into two walks.

Grand Union Canal

Grand Union Canal milepost at Hayes. The abbre-
viation refers to the Grand Junction Canal Co.

Following a brief taste on the previous walk, you’ll find yourself alongside the canal for much of this section, so now is the time to say a bit more about it. The practice of digging artificial water channels as a form of transport infrastructure dates back at least to Roman times, though the current network of canals in the UK is largely a product of the Industrial Revolution. Prior to this, transporting bulk goods long distances inland to destinations that weren’t close to the navigable sections of natural rivers involved horse-drawn wagons, rendered even slower and more laborious by the poor state of the roads.

The practice of improving rivers for navigation by dredging, removing obstructions, straightening courses and constructing locks and weirs to manage level changes also has a long history. As we’ve already seen along the Thames on the London Countryway, these activities increased during the 16th and 17th centuries with the development of trade. And digging an entirely artificial channel between two places not previously connected by water is very much like digging a cut to avoid the meanderings of a river, but on a grander scale.

With the emergence of large scale industry in the mid-18th century the need for bulk transport increased massively. Previously, large settlements had tended to grow in places that already had decent transport links like navigable rivers or coasts, but the location of the new industrial centres was dependent instead on their proximity to crucial resources like coal and iron, and many were deep inland. And with railways and powered vehicles still some decades away, new canals were the obvious solution.

The first true modern canal in the UK was the Newry Canal in Ulster, opened between the Tyrone coalfields and the Irish Sea near Newry in 1742. The first entirely artificial canal in England was the Bridgewater Canal, the first stretch of which opened between the Worsley coal mines and Manchester in 1761. The success of these and other projects sparked a boom in canal construction lasting some 60 years, helping transform the face of the country, particularly in the Midlands and north of England.

As with the railways that were to follow, the canals were almost entirely built as private commercial ventures under the authority of individual Acts of Parliament which among other things gave their builders the necessary powers to purchase land and to charge tolls to users. And like the railways, the result was a tangled and sometimes irrational network of competing routes. Most were ‘narrow canals’ with a minimum width of only seven feet (2.1 m), as these were cheaper to construct, and a new style of long, thin ‘narrowboats’ emerged to navigate them. Originally these boats were unpowered, towed by horses walking along a parallel towpath, and some of them remained so into the 20th century.

Birmingham, as is well-known, has more canals than Venice, but until the very end of the 18th century the only waterway connection between the West Midlands and London followed the Oxford Canal to its namesake city and then the Thames. Despite numerous improvements, the river was much less amenable to boats than a purpose-built canal and, with its natural meanders, notably indirect.

A number of possible routes were surveyed and in 1793 Parliament approved a proposal by the Grand Junction Canal Company. This created a new link from Braunston in Northamptonshire, on the Oxford Canal much closer to Birmingham, with the Thames at Brentford, then still a separate town west of London, shortening the journey by about 100 km. The 150 km Grand Junction was built as a broad canal with a minimum width of 14 feet (4.2 m) but the connecting Oxford Canal was narrow, so only narrowboats could make the through trip.

For some reason, MPs had preferred the Brentford route to a competing proposal direct to central London, but it wasn’t long before the wisdom of this was questioned. In 1795, with construction only just started, Parliament approved a 22 km branch from Bulls Bridge, a few steps from where the Loop first joins the canal in the previous section, to Paddington. The railway station for which this northwest corner of central London is now best known was still some decades away, but it was already a transport interchange as the western end of the New Road (today’s Marylebone, Euston, Pentonville and City Roads), London’s first bypass, opened to the City in the 1750s.

Constructed under the direction of the celebrated canal engineer William Jessop, the waterway opened in stages. The section from Brentford to Hemel Hempstead, which the Loop follows, opened in 1798, followed by the Paddington Arm in 1801. The complete route was delayed until 1811 by problems with a tunnel nearer to Braunston. By then the Warwick & Napton and Warwick & Birmingham canals, both opened in 1800, had created an even more direct route from Braunston to Birmingham. Connections were further improved with the opening by a separate company of the Regents Canal between 1816-20, providing a direct waterway link from Paddington to Limehouse in the London Docklands.

At first, perhaps unsurprisingly given the economic powerhouses it connected, the canal was hugely successful. In 1810, almost 350,000 tonnes of goods were transported along the waterway to London, and in 1831 it generated £160,000 in tolls – about £15 million in today’s prices. But in 1825 the UK’s first steam-operated railway, the Stockton and Darlington, heralded the arrival of a means of transport that was to change the landscape once again. In 1838 the UK's first intercity railway provided an alternative link between London and Birmingham, placing the Grand Junction on the sharp end of railway competition.

The commercial decline of the canal network was a prolonged process which was never quite completed, as a modest (and modestly growing) amount of freight still travels this way today. The arrival of steam power in the 1860s helped, but the only real way for the canals to compete was by lowering tolls, which meant cutting maintenance costs, in turn generating problems with safety and reliability. In 1929 the Grand Junction company merged with the Warwick canals into a group led by the Regents Canal company, with the whole length between London and Birmingham renamed the Grand Union. The new group launched a refurbishment and widening programme financed by government loans. But by then the arrival of further competition in the form of road transport had tightened the screws on the canal system still further.

The end of World War II ushered in a brave new world of state planning, and in 1948 much of the canal system, including the Grand Union, was nationalised along with the railways under the British Transport Commission, succeeded in 1963 by the British Waterways Board. By now some far-sighted people had started to rethink the waterways in terms of other purposes, such as recreation and the environment. The decline of commercial traffic created space for leisure cruisers, day trips, house boats and anglers, while towpaths once trodden by labouring horses provided a potential network of easy off-road routes for walkers and cyclists. Newly clean canals turned out to be havens for wildlife, not only in the water but in the grassy margins which provided green strips through urban areas.

Pressure groups such as the Inland Waterways Association, formed in 1946 following the publication of Tom Rolt’s influential book Narrow Boat, campaigned for this sort of repurposing, with a wave of volunteer-led projects to restore canals that had been abandoned as uneconomic. Initially the navigation authorities were unsympathetic to alternative uses, but this stance shifted as it became clear that commercial traffic was a lost cause, and the 1968 Transport Act explicitly recognised the leisure potential of waterways. Another financial lifeline has emerged more recently: many towpaths now host fibre optic cables and even high tension mains.

Grand Union Canal just south of Swan and Bottle Bridge

The cultural transformation of the waterways from utilitarian necessity to environmental asset has been dramatic. Before the second half of the 20th century few people would have visited urban canals unless they had to – they were smelly, dirty, dangerous places, particularly neglected ones that had become informal rubbish dumps. People who worked on them were regarded as a race apart. The families of boating operators usually lived on their boats, always on the move, and for generations missed out on education and literacy, becoming an isolated and inward-looking underclass. They developed their own culture, expressed among other ways in the traditional decorations of their boats. Now that culture remains only as an appropriated emblem of heritage, and middle class alternative lifestylers pride themselves on the castles and roses brightening their wifi-equipped narrowboats.

This transformation is written in the pattern of development. Most buildings more than a few decades old in the immediate vicinity of the waterway are industrial. Older residential properties either turn their back on the water or stay at a safe distance. New developments, in contrast, embrace the canal as a positive feature, with properties closer to the water sold at premium pirces. There’s a good example of this approaching Harefield West, where luxury designer dwellings overlook what was once a clogged artery of the Industrial Revolution.

British Waterways, meanwhile, succumbed to the contemporary political distaste for state agencies in 2012, when its assets, including the Grand Union, were handed to a new independent charity, the Canal & River Trust. Currently the Trust enjoys continuing government funding but its long term sustainability remains to be proved, and there may yet be another crisis period for the waterways.

Planning a canal route meant balancing several factors including directness, the cooperativeness of landowners, and geography. Canals aim to be as level as possible so the flow of water is kept to a minimum; any significant change in level requires the use of locks, which are expensive to engineer and maintain and slow progress for boats. One solution is to follow river valleys, also providing a nearby source of water, and the Grand Union adopts this strategy in several places. At Brentford it’s essentially a canalised section of the river Brent for a while, but the Loop joins it where it traverses river valleys to pick up the river Colne. The bridges are all numbered and the sequence starts in Braunston so we follow it in reverse, starting at number 200, Station Road Bridge in Hayes.

Stockley Park

The view from Stockley Park

Canal walking isn’t to everyone’s taste. Well-defined towpaths with the minimum of sharp turns make for easy progress, with passing boats and wildlife for interest, and in an urban area there’s an odd sensation of alternative geography, of hidden threads stitched within the fabric of familiar streets. But the lack of challenge and the consistency of the surroundings can make you yearn for a bit more variety. The Loop responds by not sticking religiously to the towpath, instead heading off on intermittent detours to show you more of your surroundings.

There are also a number of diversions you could make yourself. Soon after rejoining the towpath, a Legible London-style sign points off to the Old Vinyl Factory, the former EMI record plant discussed at the end of the last section. EMI also has a connection to Lake Farm Country Park on the right, as between the late 1940s and early 1990s it tested radar equipment here. A testing tower, concrete surfaces, a derelict trailer and other remnants still stand on a site that has also been a common, a brickworks and, more recently, hay meadows.

Hillingdon Council bought Lake Farm in 1998 following a local campaign to save it as open space, installing among other things a much-loved sculpture of a skylark by Ben Dearnley, later one of the official artists for London 2012. There was another local storm in 2014 when the council authorised the building of an academy primary school in the northeast corner.

The first official detour starts just a little way further along, venturing through an even more intriguing space that’s also associated with the brick industry. What’s now Stockley Park was once arable land and later cattle pasture, until the 1650s when then-owner John Bennet, Charles II’s deputy postmaster, had it inclosed as a deer park, gardens and ‘furze ground’ where gorse was grown as winter fodder for deer – this last is commemorated in a contemporary street name, Furzeground Way.

That all changed when the excavation of the canal uncovered a particularly fine source of brick earth, as well as providing a convenient means for transporting it. Bricks made here were used among other things in the building of Kensington museums; known as Cowley Stocks, they eventually gave rise to the current name.

Following the exhaustion of the brick earth in the early 20th century, the site was used for gravel extraction and then for landfill, leaving a polluted wasteland. An ambitious redevelopment scheme for the 180 ha site was launched in 1985, creating the present prestigious, hi-tech business park with its innovative architecture set among lakes, public green space and a golf course, finally opened in 1993. Among the tenants are such weighty international names as Apple, BP, Canon, and GlaxoSmithKline, attracted both by the amenities and the closeness to Heathrow Airport.

This was a major landscaping project, with four million cubic metres of rubbish, clay and gravel transported over 18 months from the business park zone in the south, nearest the canal, and used to shape the surrounding green spaces. New topsoil was created artificially on site by mixing local clay with imported manure, seeding and ploughing back in the initial grass crops, and introducing over one million earthworms.

Suspension bridge, Stockley Country Park

It’s an odd place to walk around, with even its parkland and water features self-evidently designed to complement striking buildings by leading architectural practices like Fosters and Arup – a little like a vision of the future from a 1960s film. The oddness is accentuated by the fact that all the buildings are for business use: apart from a Wetherspoon pub, a gym, a couple of shops and the golf course clubhouse, they’re all offices, warehouses and wokshops. The master plan was prepared just as planners’ preference for strict land use zoning was going out of fashion, and had it been delayed by a few years, housing would surely have been included in the mix, creating a more lived-in feel.

That said, it’s attractive in its own way, and the effort put into creating the green space is praiseworthy. The Loop passes the remains of the dock that once served the brickworks, now a water feature, and soon picks up a precisely regimented avenue of lime trees, intended to invoke the formal gardens of John Bennet’s time. If you follow these to the end, you’ll find the hub of the site, where the pub and shops overlook a lake, but the Loop heads off on a track shielded from the golf course by a substantial hedge to cross a landmark suspension bridge which links the two halves of the site across a bisecting road. Further development is currently taking place on a northern extension of the business park here.

On the other side the trail passes close to a viewpoint atop a grassy hill which, thanks to all that topsoil engineering, displays no clue of its true nature as the biggest pile of rubbish in the park. From here there are views towards the Colne Valley and Chilterns as well as of the comings and goings at Heathrow, from a more comfortable distance than experienced on the previous section.

Another hedge-lined track successfully conceals not just the golf course on one side but the grounds of Uxbridge Football Club on the other before returning you to the road and to a much older industrial area, where expanses of giant utilitarian sheds bearing rather less glamorous names spread backwards from the canalside, punctuated by the occasional residential terrace.

Along Horton Bridge Road, the Brickmakers pub, currently abandoned, recalls in its name the once-favoured local industry. Opposite is the John Guest factory, a name well-known to plumbers as a leading manufacturer of valves and connectors. The Loop rejoins the canal at Horton Bridge itself, still one of the original quaint humped white bridges, bearing the number 193.

Update October 2017. A new path, Weston Walk, opened early in 2017 in connection with a new development, now provides a direct connection from Stockley Park to the towpath near Horton Bridge, with no need to follow roads through the industrial area. I've updated the route description to include both options. Read more here.

West Drayton and the Slough Arm

Cowley Peachey Junction: the Grand Union running left to right and the Slough Arm in the background. Packet Boat
Marina is behind the grass bank top right.

The next bridge, Colham Bridge, carries West Drayton High Street, with an option to duck out at the similarly named station, the next one down from Hayes & Harlington on the Great Western Main Line, discussed in the last section. It’s here that the canal and the Loop start to bend north, tracking the contour of the Colne valley. The waterway marks the division between Yiewsley, to the north, and West Drayton to the south. The latter began as an ancient Middlesex parish, one of the westernmost in the county, bounded by the river Colne which long divided it from Buckinghamshire. The name likely indicates a place where boats were dragged to and from the river.

For much of its history, it was a rather isolated agricultural village with a few small mills, and there are still 17th and 18th century houses, mainly clustered around the old village centre now known as the Green, a conservation area to the southwest. Visiting train travellers in the late 1830s could still find geese, pigs and donkeys on the green, but industry had already colonised the canalside and the railway soon generated a new suburb spreading out from the station, where you’ll find most of the shops and services today. James Thorne’s Handbook to the Environs of London in 1876 observed how the village's remaining rural charms were undermined by “sulphurous and manury smells from brickfields, canals, and wharves.”

Another trail, the 26 km Beeches Way, starts at West Drayton station and briefly runs along with the Loop. The Way was a Buckinghamshire initiative, one of a number of signed walking routes in the county developed in the 1970s and 1980s by Ramblers and voluntary groups working with the council. It actually starts just in London and finishes just in historic Berkshire, at Cookham in the Royal Borough of Windsor and Maidenhead. It’s so named because it crosses Burnham Beeches, one of the City of London-owned green spaces outside Greater London itself. Among other things it provides a signed link between the London Countryway and the London Loop, and with the Grand Union Canal forms a short cut between two points on the Thames Path, at Brentford and Cookham.

There’s one more bridge, the picturesquely named Trout Road Bridge, and a swathe of recent waterside development, to go before the next diversion, although for a while at least this is also along a towpath. At Cowley Peachey Junction, a branch canal, the Slough Arm, leaves to the west. Several contrasting environments meet here. To the southwest are the wooded wetlands of the Colne Valley Park. Opposite, on the north side of the Slough Arm, is Packet Boat Marina, opened on the site of another contaminated gravel pit in 2003 and now bright with the colours of privately owned narrowboats. To the right, east of the Grand Union, is a retail park boasting the likes of Argos, Curry’s and a giant Mercedes Benz dealership.

The marina is named after the lane on which it stands, which in turn is named for the ‘packet boats’ that once plied the canals alongside more familiar narrowboats carrying bulk goods. The packets in question were small parcels, but the boats were better known for carrying passengers. Indeed they were one of the earliest forms of mass public transport, running to a published timetable. In the early 19th century a packet boat service departed daily from Uxbridge to Paddington and vice versa, but was never a great success as the journey took too long, so was soon supplanted by rail and road improvements.

The 8 km Slough Arm was one of the last canals to be built in Britain, opened in 1882, long after the early 19th century boom. Its main purpose was to carry bricks and other building materials from new brickworks at Slough to the ever-expanding building sites of London. But as the raw materials were exhausted, traffic steadily declined from a peak in 1905, with commercial use ceasing in 1960, after which it was left to decay. British Waterways initially classified it as a ‘remainder canal’, slated for closure, and Slough council proposed to fill in and build on part of it, but it was saved by a local campaign and reopened in 1975. Today there’s even an ambition to extend it by 3 km through Slough town centre to connect with the Thames, though with no funding currently assigned.

Frays River, visible bottom left, with the Slough Arm crossing it on an aqueduct and a World War II pillbox beyond.

It’s always fun when one waterway crosses another on an aqueduct, and the Slough Arm has three such examples, although the Loop only stays with it long enough to encounter one. This is the crossing of the Frays River, actually a loop of the Colne between West Drayton and Uxbridge. Its exact history is unknown but it is likely at least semi-artificial. It takes its name from a 15th century landowner, John Fray, but long predates its namesake: it could have been dug as far back as late Saxon or early Norman times to feed mills at Uxbridge. Just beyond it a World War II pillbox still stands beside the canal.

The Loop leaves the Slough Arm at the next bridge, a lovely spot where Trout Lane, now little more than a footpath, crosses the canal and heads deep into the green surrounds of the Colne Valley Park.

Colne Valley Park

Gulls wheel over Little Britain Lake, Colne Valley Park

The Colne Valley is one of London’s two long-established regional parks. The other, the Lee Valley Park on the other side of the city to the east, is also draped about a major Thames tributary running roughly north-south (a third regional park, the Wandle Valley Park, is now being developed along another Thames tributary in southwest London, this time running south-north). These two stand almost like bookends to the capital: both straddle the boundary and include parts of neighbouring counties, except that while the Colne Valley clings to the rim of suburbia, the Lee Valley digs deep into the inner city, between Bow and Stratford.

The eastern park’s more urban character and its proximity to a denser population might explain why it’s rather better-known and better-supported than its western counterpart. Certainly, its open spaces seem all the more miraculous. But the Colne has much to offer too, with numerous surprisingly quiet and secluded places within easy reach of transport, and its own role in determining the texture of the edge of London.

Both parks share a legacy from rich deposits of gravels laid down in the last glacial period, quarried millennia later as building materials to service London’s physical growth. As the gravels became exhausted the workings were abandoned, leaving behind an inhospitable and dangerous landscape of often polluted pits. But as the demand for outdoor recreation and green space for London grew, these wastelands were reimagined. Initially their main value was assumed to lie in water-based activities like fishing and boating, but tree-lined banks also made ideal spaces for walking, cycling, playing and enjoying nature.

As discussed in some detail in my account of the London Countryway, the idea of regional parks followed on from the National Parks created by postwar legislation. The latter were designated because of the character of their countryside, irrespective of their location, while regional parks, which never gained statutory recognition as a category, were specifically intended to serve big city populations.

The Lee Valley Park was first envisioned in Patrick Abercrombie’s utopian Greater London Plan of 1944, but only eventually happened because of the determination of local campaigners. Abercrombie only mentioned the Colne in passing, commenting on its numerous channels, but proposals for the Lee surely inspired a 1965 report by Hillingdon council noting the recreational potential of numerous abandoned gravel pits along the river. This report, and support from the Greater London Council, resulted in a conference of the various local authorities concerned later that year, and the park began to take shape in the 1970s.

The official source of the Colne is an underground stream that emerges at North Mymms in Hertfordshire: some of the water surfaces from the swallow holes which the London Countryway passes on its way to Welham Green. But the drainage basin stretches far into the Chilterns, fed by chalk streams like the Chess, Gade, Misbourne (the source of which is also on the Countryway at Great Missenden) and Ver. It has a watershed to the north of Tring with the next great river basin north, the Great Ouse, which drains towards the Wash. The Colne, as already mentioned, runs roughly north-south, joining the Thames at Staines on Thames.

The initial plans for the park covered just over 10,000 ha, since expanded to the current 11,130 ha. It’s a strip of land running from the fringes of Chorleywood and Rickmansworth in the north to Staines, stretching to the Chalfonts, Gerrards Cross, Slough and Datchet in the west and Harefield, Ruislip, Uxbridge and Heathrow in the east. Most is in Buckinghamshire, with parts in Hertfordshire and the London Borough of Hillingdon and small portions in Surrey and Slough (formerly Buckinghamshire, then Berkshire, now a unitary authority).

While its eastern sister has the advantage of a statutory authority with modest fundraising powers, set up by its own Act of Parliament, the Colne Valley Park has always been a more informal partnership between councils, land managers and voluntary groups, which might explain its more sporadic levels of support and its relatively weak identity. It has coped with the age of austerity by creating a Community Interest Company, set up in 2012, which commissions the environmental charity Groundwork to manage the park. The broader vision of a large, connected stretch of public space seems to have been put on hold in favour of concentrating on a number of key sites, some of which we’ll pass on today’s walk.

The history of the park’s own flagship walking trail is symptomatic of the stop-start approach. In the late 1980s, a trail called the Colne Valley Way from Staines to Uxbridge was signed on the ground and promoted in free leaflets. Subsequently, though, it was rather neglected, and in the early 2000s the park management announced it would be superseded by a new route for riders and cyclists as well as walkers running the whole length of the park to Rickmansworth, with branches to other transport interchanges, known as the Colne Valley Trail. But though this is now signed in various places, it hasn’t been completed to the promised extent, and neither trail has a proper description on the park website.

It’s all very confusing, particularly as other trails, including the Loop, Grand Union Canal Walk and various circular walks, share some of the paths used. The Way and the Trail combined, incidentally, effectively form part of an alternative western waterside route for the Loop, by continuing upstream on the Thames Path from Kingston to Staines and then turning north.

Trout Lane leads to the southwest corner of Little Britain Lake, a typical example of one of park’s reclaimed gravel pits and a well-known local beauty spot. Originally dug in the 1930s between the Colne and Frays River, the pit was turned into the current 6 ha lake in the 1970s and first operated as a private fishery, but since 1983 the site has been managed by Hillingdon council as a public space and a designated site of local importance for nature conservation, with an accessible path added in 2005. The islands are largely artificial, created with local hornbeam, birch and willow wood to attract water birds. The name refers to the lake’s supposed similarity in shape to Great Britain, at least as reflected in a mirror, and with a very liberal definition of similarity.

Just inside Buckinghamshire, alongside the river Colne north of Little Britain Lake.

Not far from the lake, the Loop crosses the river Colne itself, and briefly enters the district of South Buckinghamshire, continuing north on a delightful woodland path along the river’s west bank. The county can trace its history back to Saxon times when it was part of the Kingdom of Wessex – specifically, that part that looked to the fortified borough of Buckingham, in the north of the present county, for defence against the Danes. The name derives from an Anglo-Saxon personal name, Bucca, meaning ‘the shire of Bucca’s home’, though the county town has been Aylesbury since Henry VIII’s time. Both the county council logo and the official coat of arms feature swans, apparently because the birds were once bred in the county for the royal dinner table, and you’re bound to encounter a few live examples on this very watery walk.

Coal post on the present London boundary, at Clisby's
Bridge near Iver.

The path crosses back to the Hillingdon side of the river along Iver Lane at Clisby’s Bridge, rebuilt in 1840. On the left just past the bridge parapet is the first surviving City of London coal tax post actually on the trail itself (though we passed close to a couple on Coulsdon Common, and they’re discussed in more detail on the London Countryway).

It was placed here in 1861 when this part of what was then Middlesex was included in the Metropolitan Police District, and is one of a few such posts that now stand on the contemporary boundary of London. The inscription “ACT 24&25VICT CAP42” refers to the legislation that defined this boundary, The London Coal and Wine Duties Continuance Act 1861, by the years of Queen Victoria’s reign in which it was passed, and the chapter number.

Uxbridge

The next stretch of path has been recently widened and surfaced and is easy going, with the green-clothed river on one side, but with industry in the form of the daftly named Chiltern Business Village (not really in the Chilterns, not really a village) on the other. It’s part of a broader industrial area known as Uxbridge Moor, which once was indeed an open area of rough ground on the edge of Uxbridge town until the canal was dug through it. Warehouses, oil and mustard mills, glass and gas works followed. Today the industry is lighter, though there’s still a sizeable paint and coatings plant run by Trimite.

The path bends east away from the river and the Loop follows an industrial estate drive, then narrow Culvert Lane, lined on one side with what once were modest workers’ cottages but are now desirable properties. The eastern section of the street forms part of Uxbridge Moor Conservation Area. Opposite the end of Church Lane, a path on the left will give you a glimpse of St John’s church, a simple but elegant Commissioners’ Church built of local brick in 1838 to a design by Henry Atkinson to serve the expanding population. It was closed in 1993 and the building converted to offices and flats.

Uxbridge Boat Centre at Uxbridge Moor dates back to the Victorian heyday of commercial traffic on the canal.

Culvert Lane takes the Loop back to the canalside, diagonally opposite Uxbridge Boat Centre. Back in the 1880s this was a boatyard belonging to West Bromwich-based Fellows, Morton & Clayton, who became one of the biggest and best-known commercial carriers on the canals. The company continued to build and repair boats here until its liquidation in 1948. After this the yard fell into dereliction until rescued in the 1970s to serve growing leisure traffic, incorporating a traditional chandlery.

Fake art deco: the Parexel Building at Swan and Bottle Bridge, Uxbridge

From here the towpath continues under Dolphin Bridge to Swan and Bottle Bridge, where the old Oxford Road crosses the canal on its way out of Uxbridge. It’s named after the adjoining pub, now in a modern building but with a history as a coaching inn dating back to at least the 1760s. The name likely derives from a merger of two adjoining pubs, the Swan and the Leather Bottle.

The Paraxel building on the other side of the canal from the pub looks at first glance like 1930s art deco but is actually a 1991 pastiche built for a pharmaceutical testing company based in Boston, Massachusetts. Look out also for an attractive partly-mirrored Millennium mosaic under the bridge itself.

Swan and Bottle Bridge marks the official end point of section 11 of the Loop and a signed link from here follows the Oxford Road into Uxbridge town centre. In fact the site of the bridge from which the town takes its name is a few steps in the opposite direction from the Swan and Bottle, where the main road crosses the Colne. The ‘Ux’ is derived from a Saxon personal name, Wixan, although the bridge itself is known as High Bridge. Unsurprisingly given the proximity of the river, human habitation in the area dates back a long way – the excavation of the Chimes shopping mall in the town centre in the late 1990s unearthed Bronze Age remains.

Uxbridge is an important local shopping centre, but do try to avoid pushing
your trolley into the canal.

Uxbridge isn’t mentioned in the Domesday survey, but by around 1200 there was already a chapel of ease of Hillingdon church standing on the Oxford Road. This grew into St Margaret’s Church, which has a 14th century tower and 15th century nave, though is much rebuilt.

Uxbridge then was simply an outlying hamlet of Hillingdon but gradually became an important town in its own right, boosted by traffic on the road (the town boasted 20 inns in 1648), a market established by the late 12th century, and later by industry, including flour milling. Today the reversal of roles is complete: Uxbridge is the administrative centre of the London Borough of Hillingdon, and one of the biggest shopping and commercial centres in outer west London.

The town once had three railway stations: Vine Street (1856), on a branch from the Great Western, closed in 1962 as an early victim of the ‘Beeching Axe’; Belmont Road, opened by the Harrow and Uxbridge Railway as a branch from the Metropolitan Railway in 1904; and High Street (1907) on a branch from the Chiltern Line, closed to passengers in 1939 and closed completely in 1964. Belmont Road was replaced in 1938 by the current London Underground station a little to the south. This station on the Tube’s western extremity survives today, a large and splendid red brick building designed by celebrated Underground architect Charles Holden, with spectacular stained glass friezes above the ticket hall. It’s a fitting place to end your Loop walk if you choose.

Denham

Denham Deep Lock

Pushing on, just beyond Swan and Bottle Bridge, the Colne merges briefly with the canal, and the Buckinghamshire boundary swings in to cross the towpath and follow another branch of the Colne, known, for obvious reasons, as the Shire Ditch. So Denham Yacht Station, with its vaguely boat-shaped single storey building, is actually in Denham, the first parish on the other side, in Buckinghamshire. But then, confusingly, so is Uxbridge Lock, the first canal lock encountered on the Loop, and the only one in South Buckinghamshire District.

The area to the west of the lock, between the canal and another loop of the Colne, was historically the site of two flour mills, the Old Mill and the New Mill, the latter built over an older facility known as Hubard’s Mill in 1835. The site, which includes a fine 18th century mill owner’s cottage, is sometimes known as King’s Mill, not for any royal connections but after a former proprietor, William King. Milling on the site only finally ceased in 2001 but the brand of sliced bread that originated here can still be found in every supermarket.

The Colne leaves the canal again to the left just before both pass under a long, low viaduct that carries the A40, the modern day successor of the Oxford Road, over the valley. This section is part of Western Avenue, the 1930s arterial road running west from White City, but has been widened and rebuilt since. The towpath now runs between the canal and the river, the latter never far away on the left, towards Denham Lock, soon with Denham Country Park beyond. Here the river Misbourne joins the Colne, and a few paces further north the Loop completes the second and last of its brief sidesteps into Buckinghamshire, returning to Hillingdon for the rest of the section.

Denham also has an Anglo-Saxon name, from ‘dene-ham’, settlement in a valley. It appears in the Domesday survey, and between the 13th century and the Dissolution in 1540 it was an important village just off the Oxford Road which was largely the property of Westminster Abbey. The historic village centre is westwards along the Misbourne, while the station, opened in 1906 on what’s now the Chiltern main line, is some way to the northwest, surrounded by its own suburb, Denham Green.

The village is probably best known today for its association with the film industry, which naturally gravitated to the leafy fringes of west and northwest London. While Elstree, further along the Loop, has the strongest claim to being the ‘British Hollywood’, Denham Studios, founded by legendary Hungarian producer Alexander Korda in 1936, produced numerous British classics, including Michael Powell and Emeric Pressburgers’s A Matter of Life and Death (1946) and Laurence Olivier’s Henry V (1944). Film production ceased after 1952, and in the late 1970s the site was redeveloped as an industrial estate known as Broadwater Park. It’s some way off our walk to the northwest – if you want to visit, Widewater Lock, further along the towpath, is the more convenient point to make a detour.

The country park is a fragment of the old manorial estate of Denham Court, which was split up in 1670. The southern part, along the Misbourne, was attached to a fine 17th century mansion, Denham Place, possibly on the site of the original manor house and still standing today at one end of the old village. Poet John Dryden was a frequent visitor in the 1690s and described the place as “one of the most delicious spots in England.” Despite mainly being in Buckinghamshire, the estate was bought in 1936 by Middlesex County Council and inherited by the Greater London Council, transferring to Buckinghamshire on the GLC’s abolition in 1986. Another mid-17th century mansion, now known as Denham Court, stands to the north, closer to the Colne. Following a period of postwar neglect, since 1992 this has been the clubhouse of a prestigious golf course created by Japanese brewery Asahi.

A path to the left just before the lock leads across the Colne and through the country park to Colne Valley Park Visitor Centre about 10 minutes away – it’s a worthwhile detour if you’re after information about other features of interest in the area.

This path is also the start of the South Bucks Way, one of the early routes pioneered by keen walking volunteers in the county from the 1970s. This largely follows the Misbourne Valley for 37 km from Denham Lock to Coombe Hill on the Ridgeway National Trail, in the Chilterns west of Wendover. From here if you dodge a little way along the Ridgeway to Great Kimble you’ll find the start of the North Bucks Way to Wolverton near Milton Keynes, which in turn is the southernmost of a connected series of walks known as the Midshires Way, north through Middle England to Manchester with connections to the Pennine Way. So from Denham Lock you could if you wished walk signed trails all the way to the Southern Uplands in Scotland.

Denham Deep Lock is the deepest on the Grand Union, shifting boats up by almost 3.5 m so the canal can reach an aqueduct over the Frays River just before it joins the Colne. Fran’s Tea Garden by the lock cottage is a popular local destination, while the woodlands on the other side of the canal form part of an extensive Local Nature Reserve (LNR) including two Sites of Special Scientific Interest. The next bridge along is known as Turnover Bridge, a generic term for any bridge where the towpath changes sides, although in this case it marks the end of a stretch with paths on both sides of the waterway.

The Loop crosses the bridge on a third diversion away from the towpath, continuing north for a while parallel to the canal just within Denham Quarry, now converted to five Hillingdon council-owned fishing lakes also popular with overwintering birds, and part of the LNR.

Chiltern Main Line viaduct at Denham Quarry, soon to be joined by a rather large example carrying HS2.

A tall viaduct takes the Loop under the Chiltern Main Line, opened as the Great Western and Great Central Joint Railway (GW&GCJR) in 1906 as part of a route from Marylebone and Paddington to Birmingham and the north of England, in competition with the London and North Western Railway’s line from Euston. Across the next lake to your right past the viaduct is the Hillingdon Outdoor Activity Centre: this evolved from a sailing base opened in 1950 on one of the earlier flooded gravel pits in the valley and is now an educational charity.

The 1906 viaduct is now accepted as complementing the landscape, but plans to construct a modern successor of the London to Birmingham rail routes across the valley have met vociferous local opposition including from the Colne Valley Park. High Speed 2 (HS2), the proposed high speed rail line from Euston, is currently planned to cross the area on a new 3.4 km viaduct. This will cross the Loop on a northwest-southeast axis just about where the trail turns away from the canal past the corner of the next lake. It’s likely there will be disruption to the route and possible diversions during construction, which could begin in mid-2018. The Activity Centre is due to be moved across the Buckinghamshire boundary.

More colourful narrowboats are visible through the fence on the left, moored up at Harefield Marina. Like the activity centre, this opened in the early 1950s but fell into neglect in the next decade, and was revived and reopened in 1985. A little further on, the Loop winds north again, running through rough woodland and along old quarry tracks, passing a curious earth-filled boat hull colonised with trees, to arrive in South Harefield.

Harefield

The view from Coppermill Bridge, Harefield West, looking north along the Grand Union Canal, with former mill buildings and modern flats under construction right.

Harefield is a sprawling ancient parish occupying the extreme northwest corner of London (and, formerly, the extreme northwest corner of Middlesex). It’s centred on a large village green by a crossroads on a raised plateau above the Colne to the east, though its parish church is about a kilometre south, further down the hill. It’s another Anglo-Saxon name, meaning military field, and is mentioned in Domesday as a relatively large village. Its most famous feature is arguably Harefield Hospital, a specialist heart and lung hospital established in 1937, where the first heart and lung transplant in the UK was performed in 1983.

This area’s relative remoteness from railway lines restricted development and today, aside from the clusters around the village itself, South Harefield and Harefield West where this section ends, it’s one of the most rural parts of the Hillingdon. Ironically, you don’t really see this from the Loop, which runs either along the canal or through built-up streets, but if you catch the bus back to Uxbridge, you’ll find it’s a surprisingly long trip on country roads through open fields.

Black Jack's Mill: note the mill race still running beneath the building.

The trail rejoins the canal at Widewater Bridge, by Widewater Lock, the first of three locks providing picturesque settings along the last stretch of today’s walk. The brick and slate lock cottage, built around 1800, is now Grade II listed.

Further along is Black Jack’s Lock, with its adjacent part-17th century timber-framed mill house and cottage above a branch of the Colne, also Grade II listed. You can still see the mill race running beneath. In recent years the building has housed a restaurant and an upmarket bed and breakfast but last time I passed it was up for sale.

To the left of the canal here are more lakes forming part of the Mid-Colne Valley Site of Special Scientific Interest mainly because of their bird life. One of the largest expanses of water in the regional park, Broadwater Lake, between Widewater and Black Jack’s locks, is operated partly as a fishing lake, partly as a nature reserve managed by the Herts and Middlesex Wildlife Trust. Further on, approaching Harefield West, the canalside becomes built-up again, with aforesaid luxury dwellings on the right, Behind these, a triangle of chalk grassland, unusual at this distance from the Chilterns, rises up to the plateau. Known as Coppermill Meadow or Mount Pleasant, it’s also part of the SSSI.

The London Loop’s final dalliance with the Grand Union Canal and the river Colne ends just before Coppermill Bridge, next to the large and handsome Coy Carp pub, originally built to service the canal and formerly known as The Fisheries. Long distance walkers could follow in the hoofprints of the old tow horses along the Grand Union Canal Walk from here all the way to Gas Street Basin in Birmingham. The towpath also provides a link to the London Countryway at Kings Langley.

It’s worth walking on for a few steps under the bridge and surveying the scene at Coppermill Lock, with the Colne to the left, and a broad basin and weir serving the former mills to the right. A corn mill stood on this site at least since the early 1600s, which was either supplemented by or became a paper mill in the late 17th century. It operated as a copper mill from 1803-1870, then again as a paper mill and, from 1890, an asbestos works. By the 1950s several rubber companies were based here. Today the site is in the final stages of conversion to an upmarket residential area known as Royal Quay.

Take care as you cross the narrow bridge and the winding lane beyond it, with one-way traffic controlled by lights. Where the road widens, you walk past the former mill owner’s house on the left, a fine Grade II listed classically-styled two storey Georgian brick building that was later used as the rubber company offices and is now being turned into flats. The Hillingdon Trail, introduced in the next section, briefly rejoins here. The section ends a few paces further on, before the Loop starts to climb from the valley along Summerhouse Drive, towards the rolling fields of Hertfordshire.

Harefield West bus island with London Loop board visible just left of centre, and the Buckinghamshire side of the Colne Valley rising above the hedge on the left.

This is one of the few Loop sections without a rail connection – instead there’s a bus island nearby. Until recently there were no Sunday buses so Loop descriptions also describe a shortish link onwards to Harefield village centre, which is worth a look if you have the time, and offers a wider range of food, drink and other services.

• Download full route description (PDF)
• View Google map
• Official Transport for London pages:
  Hayes and Harlington to Uxbridge
  Uxbridge to Harefield West