During excavations carried out in the 'small town' of Baldock by Gil Burleigh between 1978 and 1994 (Burleigh and Fitzpatrick-Matthews 2010, 9-28; Figure 1), a surprising sequence of very late deposits and features was recognised on a site known as California, the name of the nearest street (Fitzpatrick-Matthews and Burleigh 2010). Here, a deeply stratified sequence was revealed in a doline (a periglacial hollow) that began in the Middle Iron Age and continued well past the 4th century. Before these discoveries, Baldock was not known to have good late Roman sequences. Indeed, Ian Stead's work from 1968 to 1972 appeared to suggest that the town had entered a terminal decline in the later 4th century, and that by 400 it had been abandoned (Stead and Rigby 1986, 87).
The sequence at California had been protected from the post-Roman ploughing that had devastated almost all the areas investigated by Stead and remains one of the few locations in the town where Roman surfaces have survived. These surfaces included several cobble layers that completely sealed the earlier deposits within the doline, allowing the sequence to be dated (principally from ceramics and coins) and establishing a late 4th-century horizon. This horizon was cut by a number of features, including quarries and roadside ditches, which were themselves sealed by further deposits or cut by later features. During initial post-excavation work in 1983, Jonathan Drake and Gil Burleigh were able to recognise a series of phases of activity on the site that clearly post-dated 400.
In addition to the usual 'residual' Roman material, these very late features and deposits contained distinctive pottery fabrics that did not occur earlier in the sequence. Had they been assessed quickly, they would probably have been dismissed as residual later prehistoric ceramics, but careful analysis showed that none of them occurred in contexts dated earlier than 400, principally on the basis of coinage and stratigraphic association. Of course, in the light of the very late date of these fabrics, the initial assessment of 'residuality' for supposedly 'late Roman' material may need to be revised, particularly with forms and fabrics known to be among those represented in 'final Roman' assemblages elsewhere.