This one at Castlegowan is circular, about 21 metres across, and its enclosing limestone bank still stands to a height of 1.2 metres on the exterior side. No fosse, the defensive ditch that commonly accompanies earthen ringforts, is visible at ground level, which is typical for stone-built examples where the wall itself provided the primary boundary. Two courses of large square-cut limestone blocks, averaging roughly 40 centimetres across, survive along the external base of the bank between the south-east and south-west, giving a rare glimpse of the original facing that would once have given the structure a far more imposing appearance.

The broader picture of the site is one of gradual alteration over many centuries. The western and north-western sections of the outer bank have been eaten into by small quarries, the stone presumably taken for field walls or farm buildings nearby. Indeed, modern drystone walls have been built directly on top of the bank along the north-west to north-east arc, so the ancient boundary and the working agricultural landscape have become physically merged. A narrow laneway runs along the outside of the bank on the eastern side, and the original entrance to the enclosure can no longer be identified. Perhaps the most quietly arresting detail is inside: to the west of centre, there is a blocked entrance to what is recorded as a possible souterrain. A souterrain is an underground stone-lined passage or chamber, typically associated with early medieval settlement, used variously for storage, refuge, or both. That this one has been sealed off rather than excavated means whatever it contains, if anything, remains unexamined.