Beneath it, built into the exterior face of a rath, the remains of an underground stone chamber are partially open to the sky, its southern wall having long since collapsed. A displaced lintel slab now slumps across the gap, and two massive overlapping lintels still roof the surviving portion. What you are looking at is part of a souterrain, an artificial underground passage or series of chambers, typically associated with early medieval ringforts and used for storage or refuge.

The rath into whose bank this structure is embedded is a ringfort, a type of enclosed farmstead common throughout early medieval Ireland, where the surrounding bank and ditch defined a domestic space. The souterrain here sits within the south-western quadrant of that enclosure. The exposed chamber is modest, roughly subcircular in plan, about two metres at its widest and only 0.8 metres high, built from drystone construction using courses of roughly laid stone. Interestingly, the north wall is built differently from the east and west walls; where the latter use five to seven courses of large, rough stones, the north wall is composed of around ten courses of noticeably smaller, thinner slabs, suggesting either a repair at some point or simply a different hand at work. Two small openings lead off from the chamber, one through the north wall and one through the east wall, both now blocked with soil. The opening in the north wall, only 0.45 metres wide and 0.23 metres high at present, appears to extend towards the interior of the rath, possibly connecting with a void recorded near the centre of the enclosure. Local knowledge holds that the eastward passage leads into a second, better-constructed rectangular chamber, which connects in turn via a short creepway to a third, smaller space beyond. That network remains unexcavated and largely unseen, its full extent a matter of inference and tradition rather than confirmed survey.