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.
