Northborough Neolithic Causewayed Enclosure, Peterborough, Cambridgeshire - Archaeological Evaluation and Assessment of Results

Wessex Archaeology

The main aim of the evaluation was to ascertain the character, date and condition of the site, as well as the extent of preservation and waterlogging in the ditches.

The air photographic transcription showed that the enclosure comprises two pairs of concentric circuits of short ditch segments and causeways, forming an inner and an outer enclosure. It is one of five causewayed enclosures within a 10km wide area, with other probable prehistoric features, including cursus monuments, ring ditches, and field systems also identified in air photographs. All of the sites are located on the wide, low-lying plain that fringes the fenland north of Peterborough.

The evaluation included a geophysical survey of the site comprising of c. 6ha of magnetometer survey, and seven evaluation trenches. The geophysical survey successfully defined the inner enclosure but most of the outer enclosure was less clearly defined, perhaps due to the variable nature and distribution of activities across
the site. The results of the geophysical survey were used to identify suitable locations for the evaluation trenches. Four of the trenches (Trenches 1, 2, 4 and 6) were positioned so as to investigate the ditches of the inner enclosure, but in each case revealed only one of the pair of ditches.

In Trenches 1, 4 and 6 the ditches appear to have silted up naturally, and the limited evidence of post construction activity includes a few sherds of pottery and charcoal on the base of the ditch, and possible dumps of soil – one organic-rich, another containing animal bone – into the infilling ditch. In Trench 2 at the west, however, there was evidence of more concentrated activity following a recutting of the largely silted up ditch. This may have been focussed on a wide causeway between ditch segments, possibly an entrance. The re-cut ditch contained a series of layers containing burnt clay and charcoal, and was sealed by a layer of material possibly from a levelled bank, these activities perhaps representing the formalised ‘closing’ of the site.

A further two trenches investigated the outer enclosure, although it was recorded only in Trench 7, and again only one of the pair of ditches was identified. This consisted of a series of short segments 1.1-4.4m long – considerably shorter than suggested by the air photographs. A marked kink in the circuit at the point of a 3m wide causeway (with a central possible posthole) may also mark a point of access. This interpretation is given some weight by the presence of bone deposits (including domestic cattle and aurochs) placed on the base of the adjacent segments.

A few sherds of Early (and possibly Later) Neolithic pottery were recovered, along with a broken leaf-shaped arrowhead and a number of flint flakes. The small animal bone assemblage, which included mainly cattle, with some pig and one sheep, and a piece of antler, provided little information about on-site activities, while the plant
remains included a few cereal grains, hazelnuts and weeds possibly indicating cultivation. Phosphate analysis of the pre-alluvial deposits suggests more intensive stock-related activities in the eastern part of the site, but these cannot be securely associated with the Neolithic enclosure.