The earthworks below the Goblin Tower are thought to be siege works thrown up during the six months siege of 1646. These are laid out on sloping ground and consist of the northern part of a crescentic bank set some 15m from the foot of the tower, and a low oval mound, some 16m by 12m, about 30m to the north-east. Between these are slight traces of other features.
It seems to be uncertain whether these works were intended to defend or assault the Goblin Tower, which was an important water source for the beleaguered castle and walled upper town (NPRN 95209, 94723). This area is shown as a park on Speed's town plan of 1610 and it is pssible that some of these features relate to a medieval or renaissance ornamental landscape.

Source: CADW Field Wardens' Reports (DE028)

John Wiles 07.03.08