The Roman Legionary Fortress had a rectangular annexe built onto its eastern side.

The rampart of the annexe was excavated on Site A/R at the Lion Walk excavation 1971-4 (ECC330). The rampart was identical to the north-south rampart of the fortress (See MCC482) except that being 4.1m across it was slightly wider. Traces of a strip of decayed wood lay at the foot of the southern edge of the rampart for 5.9m of its length. This may have been the end of the corduroy projecting beyond the face of the rampart or, less likely, the ground-plate of a timber front. The blocks which formed the revetment were 100 to 120mm thick, 180-250mm wide, and of variable length.<1>

The legionary rampart was also encountered during excavations at 7-15 Long Wyre Street in 1979 (ECC1447). Part of the rampart was removed to reveal part of the underlying corduroy. This proved to have consisted of a layer of closely packed timbers set at right angles to the direction of the rampart. The area uncovered did not extend across the full width of the rampart. Only the north face of the rampart could be plotted exactly since the other face lay beyond the excavated area.<2>

During excavation of a pipe trench in Castle Park in 1983 (ECC375), the possible remnants of the legionary fortress annexe rampart were recorded as an extensive layer of sand to the south an contemporary with the ditch. The layer was traced south for 80m. It was generally 0.2m thick but increased to 0.8m near its southern extent. The sand sealed the natural loam subsoil which was capped by a turf line. However, 'in view of the nature of the evidence the date and function of the sand must remain inconclusive'.<3>

In August 1983, a limited investigation took place prior to redevelopment at 63-3 High Street (Spensrite)(ECC569). Deposit that resembled rampart makeup of the legionary fortress annexe were observed.<4>