What makes it quietly unusual is not simply its position, commanding as that is, but what lies beneath it. Near the centre of the interior floor, a small opening measuring less than a metre across drops into a stone-built souterrain, the kind of underground passage and chamber system that Early Medieval communities in Ireland used for storage, refuge, or both. The entrance is almost improbably modest given the complexity of what follows.

The enclosure itself is a caher, meaning a ringfort built entirely in dry stone rather than earth and timber, a form particularly associated with the rocky landscapes of Munster. Its enclosing wall, roughly faced on both sides with large slabs around a rubble core, originally stood to a considerable height; at the north-east it still reaches 2.5 metres externally, and averages nearly three metres in width. The wall has collapsed considerably at the north-west and south, and loose stone covers much of the level interior. The entrance, located at the north-east and 1.7 metres wide, is flanked by three portal slabs and closed on the inner side by two large irregular slabs. Below ground, the souterrain extends in two passages: the first runs north-east to south-west for 3.5 metres, with a small semicircular chamber opening off one side wall, roofed by three lintels; the second, connecting at the south-west end, runs north-west to south-east for 5.2 metres before a rise in the floor level brings it to a stop. The whole underground system is built with the same coursed drystone technique as the walls above. The site was surveyed and documented by A. O'Sullivan and J. Sheehan as part of their archaeological survey of the Iveragh Peninsula, published by Cork University Press in 1996.