Roughly circular in plan, the structure measures about nine metres north to south and just over eight metres east to west. What survives is a wall footing rather than a standing wall, two stones wide in most places and nowhere more than thirty centimetres high, yet along the eastern arc the stones retain a regular, almost domino-like alignment that suggests they were laid with some care. The western and southern sections have largely disappeared beneath moss and encroaching vegetation, but the overall outline remains legible.

The enclosure was identified during pre-development survey work carried out by John Cronin and Associates ahead of a wind farm project at Knockanruddig by ESB Wind Development Ltd. Its likely purpose was practical and unromantic: a pen for livestock, the kind of enclosure that farmers on upland ground have built and rebuilt across the centuries with whatever stone lay to hand. Dry-stone construction, in which stones are fitted together without mortar, can be difficult to date precisely, and no collapsed rubble is visible on either side of the surviving footing. That absence is telling. The low stone base was almost certainly never the full height of the wall; sods or timber stakes would have been stacked on top to bring it to a height that sheep or cattle could not easily breach. Those organic materials have long since rotted or been removed, leaving only the stone skeleton.