A souterrain is an underground stone-lined passage or chamber, typically built during the early medieval period and associated with nearby settlement, used variously for storage, refuge, or purposes that archaeologists still debate. The one recorded here sits beside what was probably once a small hut site, and it has the particular distinction of being inaccessible at the time it was recorded, and now unidentifiable altogether.

The site sits on the edge of an old meander scarp of the Ferta river, a landscape detail that places these earthworks on ground shaped by water over a very long time. Two univallate raths, that is, single-banked circular enclosures of the kind commonly associated with early medieval farming settlements in Ireland, occupy adjacent ground here, divided by a small stream that has worn down the enclosing banks on either side. The western rath has been further obscured by a field wall built across its southern sector. In 1927, a researcher named Ua Riain noted a smaller circle within this western rath, close to the bank, measuring about 19 feet (5.8 metres) in diameter and interpreted as a probable hut site. On its eastern side, he also recorded the souterrain, though he could not enter it even then. By the time A. O'Sullivan and J. Sheehan compiled their archaeological survey of south Kerry, published by Cork University Press in 1996, neither the small circle nor the souterrain could be identified on the ground at all.

What remains, then, is a layered puzzle: two eroded raths on a river scarp, a stream cutting between them, a field wall quietly burying part of one, and somewhere in the grass, a passage that was already lost to view nearly a century ago.