This is a souterrain, a type of artificial underground passage and chamber system built in early medieval Ireland, typically for storage, refuge, or both. What makes this particular example quietly compelling is the precision with which it was recorded at a moment when it was still, at least partially, accessible.

In 1864, Pitt-Rivers and Caulfield examined the structure and described a beehive chamber four and a half feet high, its walls lined with lime and very small stones, connected to a second chamber by a drain-like opening, with a gallery rising to the surface. The Cork Constitution newspaper offered its own account around the same time, describing a covered passage two feet square opening to the south, leading to a chamber roughly four feet by three feet three inches, closed at the top, and then a further passage of similar dimensions opening into a larger chamber five feet broad and four feet eight inches high. The souterrain lies to the east of the centre of a ringfort, the circular earthwork enclosure with which such underground features are commonly associated in the Irish archaeological record. A second souterrain has also been identified to the south-west of the same ringfort, suggesting the site was once more elaborately developed than its unremarkable surface appearance now implies.

Today there is no visible trace of the structure above ground. The measurements and descriptions survive only in nineteenth-century accounts, making this one of those sites where the documentary record does more work than the landscape itself.