Rediscovering west London’s lost landscapes: Six millennia of change and continuity at Sipson Farm

This article is from Current Archaeology issue 431

Subscribe now for full access and no adverts

A century ago, land to the north and west of London was part of Sir John Betjeman’s rural idyll – but since then the area has been gradually absorbed by the capital’s suburbs and associated infrastructure, and today it is bisected by motorways and dominated by Heathrow Airport, with its attendant warehouses, car parks, and hotels. Despite such depredations, though, patches of farmland and other open spaces survive, as do the scattered remnants of Middlesex villages – but decades of excavations have revealed evidence of much earlier occupation.

Over the years, numerous large green-field sites in the Heathrow area have become available for archaeological investigation, revealing expanses of prehistoric and historic landscapes. Indeed, it is not uncommon for two or more contiguous excavation sites in the locality to span a kilometre or more. Just 500m (0.3 miles) north of the airport, Sipson Farm lies at the southern end of one such group (its immediate neighbour being the 23.6ha (58 acre) site of the former Imperial College Sports Ground, ICSG), nestled in the north-east corner of the historic manor and parish of Harmondsworth, on arable land between the village of Harlington and the M4 Heathrow spur. There, excavations by MOLA progressed at intervals, over the course of five years, as large blocks of farmland became available to dig in advance of gravel quarrying, ultimately uncovering more than 13ha (32 acres) between 2010 and 2014.

During this work, we experienced several of the problems common to excavations on gravel terraces. In these environments, cultivation has often removed traces of ancient land surfaces and occupation levels, with typically only the lower parts of features dug deep enough to penetrate into or through the natural brickearth surviving. Local ground conditions mean that bone preservation is poor, and artefacts are often scarce, so that the age of many archaeological features can only be inferred from their alignment or position in relation to others whose date is known. Nevertheless, the make-up of this particular site meant that illuminating clues survived. There are no nearby streams, with the nearest rivers being the Colne and the Crane, each about a half-hour walk respectively to the west and east. This meant that those using the site before the advent of piped water relied heavily on waterholes and wells, especially for watering livestock, and we encountered many of these features – some of which, fortunately, contained waterlogged deposits that yielded well-preserved organic finds, including rare wooden objects, and plant and animal remains. In all, the wider project exposed more than 1,800 features, representing thousands of years of human history.

Clearing the land

Our story begins in the Neolithic period, when pollen recovered from nearby sites suggests that large areas of hitherto forested river terraces were partially cleared for settlement, farming, and the construction of earthwork monuments. At Sipson Farm, the western half of the site produced no evidence of activity of this period, suggesting that this portion was perhaps still wooded at that time, but the eastern half yielded some 15 small pits and a ring ditch.

The pits contained apparently ‘placed deposits’ of struck flint and possible burnt offerings of meat (represented by sheep- and cattle-sized bone) and charred cereal grains, crab apples, sloes, and hazelnut shells. This combination suggests that the site’s early farming community practised a mix of arable cultivation and stock rearing (although no evidence for livestock enclosures of this date was found), as well as gathering fruit and nuts from the woods or possibly hedgerows. Some of the pits produced Early Neolithic Plain Bowl or Late Neolithic Grooved Ware, too, testifying to the longevity of this occupation. The ring ditch, meanwhile, produced pottery comparable to local Middle Neolithic impressed wares, suggesting that it may have been roughly contemporary with two Middle or Late Neolithic earthworks of similar scale that were previously excavated less than 300m (984ft) to the east at ICSG. These comprised a double ring-ditch and a penannular ditch, both of which were associated with cremation burials. At Sipson Farm, we found no direct evidence of a funerary function, but it is possible that this monument may have attracted similar rites.

The ring ditch had an external diameter of 15.4m (50.5ft), large enough to suggest that its construction was a team effort, perhaps by an extended family or a local community. At times this group may have also worked with others to help build the much larger monuments located nearby, such as the causewayed enclosures at Datchet (see CA 351), Staines, and possibly east Bedfont, all of which are roughly between one and two hours’ brisk walk from Sipson Farm. These sites probably provided foci for gatherings, perhaps for trading and for social or spiritual purposes. Another particularly large and enigmatic monument, which was 3km (1.9 miles) to the west of Sipson Farm, was the Stanwell Cursus. This comprised two parallel quarry ditches spaced about 20m (66ft) apart, which ran for more than 3.6km (2.2 miles), flanking a central bank (perhaps a processional causeway?). Its course has been traced from its possible terminal near Junction 15 of the M25, continuing across Heathrow’s Terminal 5 (CA 256), before disappearing beneath the modern village of Stanwell (CA 99).