A souterrain is an underground stone-lined passage or chamber, typically constructed during the early medieval period, used for storage, refuge, or both. This one leaves no mark whatsoever on the surface above it, which places it in a particular category of archaeological record: known to exist, precisely located within a broader site, and yet entirely invisible to anyone standing on the ground.

The souterrain sits within a ringfort, the remains of a roughly circular enclosed farmstead of the kind that was built across Ireland in great numbers between roughly the sixth and twelfth centuries. The relationship between souterrains and ringforts is well established; a large proportion of known souterrains were discovered within or immediately adjacent to these enclosures, suggesting they functioned as a deliberate feature of the farmstead complex rather than as isolated constructions. In this case, the souterrain occupies the western half of the enclosure. Beyond that, the ground above it gives nothing away.