One original lintel stone still sits in place along its edge, but a second has slipped from position and now blocks the way in. Whatever lies beyond remains, for practical purposes, sealed.

The opening is the entrance to a souterrain, an underground passage or chamber built from drystone construction, meaning stones laid without mortar, relying on careful placement and weight to hold their shape. Souterrains are found throughout early medieval Ireland, typically associated with ringforts, and were used variously for storage, refuge, or concealment. This one sits inside a rath, a type of ringfort defined by an earthen bank and ditch, and its position is notably close to the bank in the south-western quadrant of the enclosure. The passage or chamber, where it can be partially observed, stands roughly ninety centimetres high, enough to crouch in rather than stand. The drystone walls have held their form, even as the lintel above the entrance has not.