What makes it quietly arresting is the sheer solidity of its construction: the earthen bank still rises to 3.4 metres in height, a figure that gives some sense of the effort invested in raising it. A ringfort, for those unfamiliar with the term, is a roughly circular enclosure defined by one or more banks and ditches, typically built during the early medieval period as a defended farmstead. Thousands survive across Ireland, but this one at Cusduff retains a presence that its overgrown condition does little to diminish.

The enclosure is nearly circular, measuring 44 metres east to west and 43 metres north to south. Beyond the main bank lies an external fosse, a ditch cut into the ground to a depth of 1.2 metres, and beyond that again a counterscarp bank, a low outer ridge just half a metre high, which would have reinforced the defensive profile of the whole structure. In places, the inner face of the main bank is still stone-faced, suggesting that whoever built it had access to the local rock and the skill to use it. The entrance, a causewayed gap 5 metres wide, faces east, an orientation common in Irish ringforts and possibly connected to practical concerns about prevailing wind and light. A few metres inside the entrance lies a recumbent stone, measuring roughly 1.1 metres by 0.5 metres, its original purpose unclear from what survives.