Great Wilbraham is a Neolithic causewayed enclosure, an archaeological site near the village of Great Wilbraham in Cambridgeshire, England. The enclosure is about across, and covers about . Causewayed enclosures were built in England from shortly before 3700 BC until at least 3500 BC; they are characterized by the full or partial enclosure of an area with ditches that are interrupted by gaps, or causeways. Their purpose is not known; they may have been settlements, meeting places, or ritual sites.

The Great Wilbraham enclosure was first identified from aerial photographs in 1972. An excavation was begun in 1975 by David Clarke, with a planned five-year research programme, but Clarke died in 1976 and the results from the dig remained unpublished for years. The surviving part of the archive of finds and records from Clarke's dig was reanalysed in the 2000s, and published in 2006. The site was rich in finds, including Neolithic flint, pottery from periods stretching from the Neolithic to the present day, and animal bone—mostly cattle, but also some sheep and pig. Radiocarbon dating of two samples from the enclosure found dates inconsistent with their context, and were assumed to be the result of later material intruding into the Neolithic levels. The site has been protected as a scheduled monument since 1976.

Background Great Wilbraham is a causewayed enclosure,Oswald, Dyer, & Barber (2001), p. 149. a form of earthwork that was built in northwestern Europe, including the southern British Isles, in the early Neolithic period.Whittle, Healy, & Bayliss (2011), pp. 1–2.Oswald, Dyer, & Barber (2001), p. 3. Causewayed enclosures are areas that are fully or partially ringed by ditches interrupted by gaps, or causeways, of unexcavated ground, often with earthworks and palisades in some combination.Andersen (2015), p. 795. The site's excavator, David Clarke, considered that it was probably a settlement, but the function of causewayed enclosures in general is debated.Whittle, Healy, & Bayliss (2011), p. 5. The causeways are difficult to explain in military terms since they would have provided multiple ways for attackers to pass through the ditches to the inside of the enclosure, though it was suggested they could have been sally ports for defenders to emerge from and attack a besieging force.Cunnington (1912), p. 48.Curwen (1930), p. 50. Evidence of attacks at some sites provided support for the idea that the enclosures were fortified settlements. They may have been seasonal meeting places, used for trading cattle or other goods such as pottery.

There is also evidence that they played a role in funeral rites: material such as food, pottery, and human remains was deliberately deposited in the ditches.Whittle, Healy, & Bayliss (2011), pp. 10–11. The construction of these enclosures would have required substantial labour for clearing the land, preparing trees for use as posts or palisades, and digging the ditches, and would probably have been planned for some time in advance, as they were built in a single operation.Andersen (2015), p. 807.

Over seventy causewayed enclosures have been identified in the British Isles, and they are one of the most common types of an early Neolithic site in Western Europe. About a thousand are known in all.Andersen (2015), p. 796. They began to appear at different times in different parts of Europe: dates range from before 4000 BC in northern France, to shortly before 3000 BC in northern Germany, Denmark, and Poland. The enclosures began to appear in southern Britain shortly before 3700 BC, and continued to be built for at least 200 years; in a few cases, they continued to be used as late as 3300 to 3200 BC.

Site

The Great Wilbraham enclosure is in Cambridgeshire, in the valley of the Little Wilbraham River, near the village of Great Wilbraham, east of Cambridge.Healy et al. (2011), p. 270. Two concentric ditches, about apart, each interrupted by multiple gaps, lie on a flat area on the north-facing side of the river valley,Evans, C. et al. (2006), p. 116. though the river has been diverted and no longer runs on its former path.Oswald et al. (2001), p. 59.Evans, C. et al. (2006), p. 119. The site is about across, and encloses about . Most causewayed enclosures are oval-shaped, but the two circuits at Great Wilbraham are almost perfectly circular, though many of the ditch sections (between the gaps) are themselves straight lines. Many enclosures were built on valley floors, usually positioned not far above the high water mark of the river, and Great Wilbraham fits this pattern. The site is slightly sloped towards the old river course, with the upper edge of the site at the edge of the higher ground.Oswald (2001), pp. 91–94. The enclosure is located on a sandy terrace, in Little Wilbraham Fen, a small fenland area connected to the larger Fens to the north by a stream.

Great Wilbraham was identified by J. K. St Joseph, who ran the aerial photography program at Cambridge University for many years, from cropmarks on an aerial photograph taken in July 1972,Hammond (1976), p. 10. and included on a list of sixteen possible causewayed enclosures based on observed cropmarks published in 1975.Wilson (1975), p. 183, fig. 2, pl. XX The site was listed as a scheduled monument in 1976.

A prehistoric henge was tentatively identified in an adjacent field in the 1970s, but a more recent review considered it to be a naturally disturbed area of gravel.Evans, C. et al. (2006), pp. 115–116, 159.

Archaeological investigations Clarke, Alexander & Kinnes, 1975–1976 David Clarke was one of the leading figures in New Archaeology, a heterogeneous movement to bring archaeology closer to the natural sciences, and conduct archaeological excavations in a scientific manner.Johnson (1999), chapter 3.Hammond (1976), p. 16. He had some experience of fieldwork, but had not directed an excavation until 1975, when he started a five-year project to investigate the Great Wilbraham site. John Alexander, the other leader of the project, was a very experienced excavator, and joined Clarke on the project after the plan included using it as a training ground for students.

Great Wilbraham had several advantages as a project from Clarke's point of view: it was close to Cambridge, where he worked; it was expected to be rich in Neolithic material, which was the recent focus of Clarke's teaching work; and it was planned as a way to put into practice some of the theoretical ideas he had propounded during the previous decade.Evans, C. et al. (2006), pp. 113, 115–116. Great Wilbraham was the only known causewayed enclosure to include peat deposits, and Clarke hoped that Neolithic wood might be found as a result, since peat is one of the few natural environments in which wood can be preserved.Taylor (1996), pp. 758–759. According to a later review, the excavation "was intended to be an experiment in what Clarke called total archaeology" (italics in the original). "Total archaeology" is an approach which attempts to integrate information from "all of the disciplines capable of bringing understanding" to a site;Gojda (2010), p. 216. accordingly, Clarke planned to include interdisciplinary analyses and an evaluation of the surrounding landscape and environment in the project.Evans, C. et al. (2006), p. 118.

A grant from the British Museum funded two weeks of excavation in September 1975; the prospect of finding preserved organic material was the reason for the museum's interest, and the grant came from money allocated for purchasing artefacts for their collections. Clarke assumed that the site was a settlement, despite the uncertainty about the function of causewayed enclosures, and did not mention the possibility of ritual uses in an application he made to the British Museum for funding for the 1976 season. Clarke died unexpectedly in the summer of 1976. He and Alexander never published their work, but the British Museum grant proposal records some of the details of the two weeks. A magnetometer survey was performed, and fieldwalking to recover surface finds, and a trench (GW I in the diagram) was excavated. Finds mentioned in the proposal included bones of cattle, sheep, pig, deer and wolf; worked wood; seeds; pottery sherds; and flints. A pollen column was taken—a column of soil, from a hole bored at the site, examined for changes in the frequency of pollen species, with each stratum of soil corresponding to a different period in the past.Bray & Frieman (2008), pp. 374–375. The column covered 5000 years of the peat, and demonstrated changes in the environment over the life of the site, such as the clearance of the site in Neolithic times and later pasture development.Evans, C. et al. (2006), pp. 116–118. Two more trenches were dug the following year, directed by Alexander and Ian Kinnes.Evans et al. (2006), pp. 113, 124.

Clarke's long-term plan for the site was ambitious, and could not have been achieved with the money requested in his proposal; a later review of the project identified shortcomings in the plan and execution as well.Evans, C. et al. (2006), pp. 121–122. Excavation proceeded by horizontal spits (layers of fixed depth), rather than the accepted method of stratigraphic excavation (removing the material in each identifiable layer of soil as a unit).Bray & Frieman (2008), pp. 364–365.Drewett (2010), pp. 88–89. Although excavation by spits is considered an unsound approach, the work was in other ways advanced for its time: for example, a computer program was written to render the contour topography of the site in a 3D perspective.Evans et al. (2006), p. 117.

Reanalysis by Evans et al. 2006 Some of the material from Clarke and Alexander's two seasons of excavation was preserved in an archive, which was stored in Cambridge and London. In 2006, the archive (less than half of which could be located by that time) was reviewed by a group led by Christopher Evans, a Cambridge University archaeologist, resulting in a paper that presented the results of the original dig, as well as a review of Clarke's ideas and how they were implemented in the field.Evans, C. et al. (2006), pp. 113–115.

The cropmark plot used by Clarke to determine where to dig the trenches proved to be inaccurate, and this meant the trenches were not ideally positioned. The first trench (GW I in the diagram) was intended to be bisected by the circuit's ditch, but only just overlapped it at the southern end. The plot of the cropmarks was altered, probably by Clarke, to allow for the new information, but it was still incorrect in the east, and the trench in the northeast of the site, dug in 1976, was started (as trenches GW II a & d) further outside the line of the circuit than was expected, and the trench had to be extended (GW II c, e, & f) before the ditch was encountered. In both seasons this led to more investigation of the fenland peat deposits and less of the interior of the enclosure.Evans, C. et al. (2006), pp. 122–124. The trench at the east side of the site (GW II in the diagram) was U-shaped, with two arms, connected at the southwestern end.Evans, C. et al. (2006), pp. 123, 125.

For all three trenches, the initial soil removal was done by machine until the base of the ploughsoil was reached, and the spoil heaps were examined for finds.Evans, C. et al. (2006), p. 124. Recording of finds below this level was poor within the trenches and inconsistent between them, so it was not always possible for the later analysis to be sure of the original stratigraphic position of the finds.Evans, C. et al. (2006), p. 125.

Findings