The entrance, a northeast-facing opening now smothered by briars and bushes, leads into earth-cut tunnels that extend in a southwest direction beneath the hillside. The only confirmation of what lies inside comes from local memory: one person recalled entering the chambers as a child, which places human access within living recollection, even if the entrance is now closed off on safety grounds.

The structure is a souterrain, a type of artificial underground passage or chamber found throughout Ireland, typically associated with early medieval settlement and built for purposes that are still debated. Storage, refuge, and ventilation for surface structures have all been proposed, and in practice any of these functions may have applied depending on the site. Souterrains vary considerably in their construction: some are stone-lined, corbelled affairs of considerable craftsmanship; others, like this one at Ardagh on Bere Island, are simply cut from the earth itself, relying on the stability of the surrounding soil rather than any built lining. That earthen construction makes them harder to date and harder to detect, since there is nothing at the surface to give them away. In this case, even the entrance has effectively been reclaimed by vegetation, leaving the site present but largely invisible in the landscape.