At Kilcullen in County Cork, a souterrain, one of those stone-lined underground passages or chambers that early medieval communities built for storage, refuge, or both, lies somewhere beneath the ground in the north-western corner of an enclosure. It has left no mark on the surface whatsoever, and that invisibility is, in its own way, the whole story.

The site was noted by P. J. Hartnett in 1939, though even then he recorded that the souterrain had "long since collapsed." By the time Hartnett was writing, there was presumably nothing left to see above ground, and the decades since have done nothing to change that. What remains is the archaeological record of a structure that was already a ruin when it first attracted scholarly attention, associated with an enclosure that still survives nearby.