A series of small trenches (test pits, T1-T12) was dug by contractors at the east end of the High Street during the replacement of gas mains, within an 88m stretch of the High Street. Most of the trenches were too shallow to reach significant archaeological deposits (they were rarely more than 1m deep), although part of a large Roman foundation was observed in one of the deeper trenches.<1> A large Roman wall foundation (F2) was observed in the north-eastern part of trench T3 (at the north end of St Nicholas' Street) at a depth of between 1.4m and 1.95m. It was constructed of septaria blocks with occasional fragments of Roman brick set in a hard pale brown mortar. It was not possible to examine F2 in detail and recording had to be done from street level. The exposed masonry was cut by modern service trenches to the south and west. A west-facing section of the foundation was exposed for a length of 1m. This was aligned roughly NNW-SSE. However, this edge was probably where it had been cut by a service trench and the real edges of the foundation were not visible. Although difficult to interpret with certainty, the masonry seemed most likely to be part of a large north-south foundation. Its position suggests that, while it was close to the western edge of Insula 30, it was probably not on the street frontage. A gravelly rubble spread at 1m below modern ground-level in T3 was perhaps a road surface of medieval or later date.