Visitors to the Roman regional capital of Venta Icenorum, at Caistor St Edmund, just south of Norwich, usually find themselves walking the impressive earthworks that, together with thick flint walls, once formed the settlement’s late Roman defences. This rectangle defines only part of a larger area of occupation, however, with the formal street-grid extending out beyond its lines. Excavations led by Professor Will Bowden of the University of Nottingham in 2009-2012 (see CA 270) established that these gravel streets began to be laid out from c.AD 100, possibly developing gradually over the course of the 2nd century. This period also saw the creation of a monumental triple enclosure ditch that surrounded the settlement with a circuit of c.2.5km (1.6 miles). This impressive boundary was first recognised through partial cropmarks, and before the 1990s it was thought to relate to a presumed Roman fort pre-dating the town. More detailed studies of the data by the National Mapping Programme, though, combined with extensive geophysical surveys, have documented a large, kite-shaped enclosure that is now generally accepted as civil defences dug to encircle an already-established town.
Sample trenches opened across all three ditches (exploring a section to the south of the walled town in 2012, and to the north-east in 2016) indicate that they had all been created within a short timeframe around AD 120. These once-imposing features were short-lived, however: following a period of initial silting, the ditches were partly infilled and their banks possibly slighted from the mid-2nd century or later, and by the mid-3rd to 4th century they had been reduced to shallow, linear hollows with no surviving earthworks.
As well as illuminating the chronology of the ditches, these investigations revealed evidence of ‘structured’ deposition – that is, the deliberate burial of selected material for a purpose beyond simply disposing of unwanted rubbish. In 2012, for example, fragments of pipe-clay figurines of Mercury and Venus were recovered from 2nd-century deposits in the outer ditch, while fills of the same period were found to contain an articulated human burial. The partial remains of a second individual, this time of late Roman date, were found within the ditch’s uppermost fill, and a third burial was encountered during 2019’s excavation of the ditch circuit at Caistor Old Hall.
