A souterrain, for those unfamiliar with the term, is a man-made underground passage or chamber, typically constructed from drystone walling and roofed with large flat slabs; they are found throughout Ireland in association with early medieval settlements and ringforts, and were likely used for storage or refuge. This one leaves no mark on the ground whatsoever.

In 1939, P.J. Hartnett recorded what local people told him: that there had once been accessible a small room built of stone walls and covered with large stones. Even then it was closed, though he noted surface indications that something was genuinely there. By the time the site was compiled into the Archaeological Inventory of County Cork in 1997, those surface traces had gone entirely. What survives is a second-hand description, passed through memory and recorded in a footnote, of a space that may never be investigated without excavation.