Known as Caher-na-Cath, or Cathair na gCat in Irish, it is the most northerly of a cluster of three cahers in the area, a caher being a stone-walled ringfort of the kind built across early medieval Ireland, typically between the sixth and tenth centuries. What sets this one apart from its better-known neighbours is precisely its condition: where the other two cahers in the group, Leacanabuaile and Cahergal, have both been excavated and conserved, Caher-na-Cath has been left to subside. Its enclosing bank, roughly thirty-one metres across, has lost all definition at its edges, bleeding into the boggy pasture around it. A neatly built wall of thin slabs runs along the western side of the site, and there is a suspicion, noted by surveyors, that it was constructed from stones robbed out of the original enclosure.

The interior tells a more detailed story, even in its ruined state. Three huts, all collapsed and sod-covered, occupy the space within the bank. The largest, positioned to the east, has internal dimensions of 7.6 metres by 5.4 metres, with stone facing still visible on its inner walls. At the centre of its floor there is a shallow circular depression, and local tradition holds that this marks the entrance to a souterrain, an underground passage or chamber typically used in early medieval Ireland for storage or refuge. A second hut to the north is connected to the first by a spread of fallen stone, and has a narrow entrance just 0.6 metres wide on its south-west side. A third, in the south-west quadrant, has walls that survive only 0.4 metres high but are a substantial two metres thick, with a 1.7-metre entrance gap facing south-east. The caher is built on a natural platform close to the upper edge of a low cliff on its western side, giving it a defensive logic even now, when that logic is mostly obscured by grass and time.