During observation of the excavation of a pipe trench in Castle Park (ECC375) in 1983, a shallow ditch was excavated inside the town wall towards the north end of the pipe trench. The ditch survived approximately 1m deep and over 10m wide. The edges had been much disturbed by later cultivation.
The base of a post-hole in the bottom of the ditch (see MCC1303) was thought to be associated with it.
The ditch backfill included a quantity of some very large septaria blocks and some flint nodules which were thought to represent a stockpile of unused medieval building material for repairing the town walls.
A further stretch of the same ditch was revealed 65 metres to the south. Immediately to the west of the ditch were the remains of a much denuded bank (see MCC1314).
'It is likely that the bank and ditch were the remains of the outer bailey defences of the castle. The existence of these defences is suggested by the rise and pronounced dip in ground level running northwards the Park cafe. This forms a boundary of some antiquity.'<1>

see also Arch Journal 1983 Plan of 1622 in Drury article.<2>

A parallel ditch is suggested by the 1610 map (Speeds map of Colchester) which depicts an area of free of buildings, running up from the town wall to St Helen's Chapel along the east side of Maidenburgh Street.<3>