A souterrain is a man-made underground structure, typically drystone-built, associated with early medieval settlement in Ireland and used variously for storage, refuge, or both. This one is more elaborate than many, comprising two distinct chambers connected by a narrow squeeze-passage known as a creep.

The construction is entirely drystone, meaning the walls and roof are assembled from uncut stone without mortar. The first chamber runs roughly northeast to southwest and measures 7.7 metres in length and 1.7 metres across. At its southwestern end, a creep just 0.55 metres wide forces anyone passing through to move slowly and carefully, a feature that would have made the passage defensively useful. Beyond it, the second chamber is longer at 9.5 metres, slightly narrower at 1.3 metres, and bow-shaped, curving back from southwest to northeast so that the two chambers run broadly parallel. Both chambers are entered from openings at their northeastern ends. The whole structure sits within a ringfort, the circular enclosure of an early medieval farmstead, suggesting it served the household that once occupied that settlement, though whether primarily for cool storage or as a place of concealment is not recorded.