This is a souterrain, a type of man-made underground structure built during the early medieval period in Ireland, typically used for storage, refuge, or both. What makes this particular example quietly arresting is not its scale but its construction: the passage narrows as it descends toward a chamber, the chamber itself widens oddly toward the top, and the six lintels roofing it are laid at differing orientations, as though the builders were improvising as they went.

The souterrain sits within a cashel, a circular stone-walled enclosure of the kind common across early medieval Ireland, serving as a farmstead or defended homestead. The entrance, now rubble-filled, originally opened to the south-southeast, leading into a passage roughly two metres long and just over a metre high. The chamber at the far end measures about 1.6 metres east to west and widens to two metres at its broadest point. A continuation of the chamber toward the northeast has been blocked by a boulder that collapsed from the roof, leaving that section inaccessible and its full extent unknown. The floor, particularly toward the southwest, is heavily covered in stone. Just outside the entrance, a small circular hollow roughly a metre across and forty centimetres deep has been recorded, its original purpose unclear. Within the same cashel, the remains of a possible house survive in the southern quadrant, and a further cashel and hut site lie approximately 98 metres to the west, suggesting this was once a reasonably active settlement cluster rather than an isolated structure.