The builders simply incorporated the rock face into their design, completing the remaining three sides with rough field stones, and the result is a D-shaped structure, flat along the north and curved around the rest, measuring just under ten metres in either direction. It is not large, but the choice of location is deliberate and telling: higher than the lake, drier than the surrounding ground, sheltered against the ridge, and with a clear view over the water below.

The structure was recorded by archaeologist Tony Miller in February 2012, who noted it sits approximately eighty metres north of the point where a river exits Barley Lake. The land around it is rough grazing, hemmed in by steep slopes and cliffs, which gives some sense of how remote and self-contained this spot would have felt to whoever used it. Enclosures of this kind, where a natural feature such as a rock outcrop or a stream is pressed into service as part of the boundary wall, are found across Ireland and often signal a pragmatic, opportunistic approach to construction rather than a monumental one. Whether the enclosure here served as a small farmstead, an animal pen, or something else entirely is not recorded, and the stones themselves offer no obvious answer.