Beyond it, a stone-lined passage stretches away to the north-east, its walls built in careful horizontal courses of flat slabs, three lintels still visible overhead. Nobody has passed through it in a very long time. Infill material blocks the way, and the structure does not appear on any Ordnance Survey map, existing officially only in the archaeological record rather than in the named, charted landscape most people navigate by.

A souterrain is an underground stone-built passage or chamber, typically associated with early medieval settlement in Ireland, and often interpreted as a place of storage, refuge, or both. This one sits on a slight rise in the ground about seventy metres south-east of a rath, the circular earthen enclosure that was the standard form of enclosed farmstead in early medieval Ireland. The proximity is telling. Souterrains of this kind were frequently built in direct association with raths, sometimes opening into the interior of the enclosure, sometimes positioned just outside it. The construction here, with its flat-slab walling and surviving lintels, is consistent with that tradition, though the blocked passage means the full extent of the underground structure remains unknown.