Set into the floor of the hut is an opening just over a metre wide, leading down into a souterrain, one of the underground stone-built passages that appear across early medieval Ireland, typically associated with ringforts and used variously for storage, refuge, or both. What makes this one quietly arresting is how much of its original construction survives despite its inaccessibility.

The passage runs towards the south-west and measures roughly 5.1 metres by 5 metres in plan, with a height of around 1.2 metres and walls nearly 2.7 metres thick. It is built entirely in drystone, meaning no mortar, just carefully placed and fitted stone, and the upper courses of the passage lean inward in a slight corbel before meeting a lintelled roof, flat stone slabs laid horizontally across the top. This technique, simple but structurally sound, is characteristic of early medieval construction across Munster. The hut above ground incorporates some notably large blocks into its own drystone walls, suggesting the whole complex was built with considerable effort and intention. The site was surveyed and documented by Aidan O'Sullivan and Jerry Sheehan as part of their comprehensive archaeological survey of the Iveragh Peninsula, published by Cork University Press in 1996.

The passage is recorded as inaccessible, so a visitor should not expect to enter it. What remains visible is the overgrown hut structure itself and the opening in its interior floor, details that reward careful looking rather than exploration.