What remains is an L-shaped depression, roughly 4.8 metres along its long axis, with two large stone lintels still sitting in place at its western end, as if waiting for a roof that is mostly gone. A souterrain, for those unfamiliar with the term, is a man-made underground stone-lined passage or chamber, typically associated with ringforts and built during the early medieval period, most likely for storage, refuge, or both. This one was recorded on the third edition of the Ordnance Survey six-inch map, published between 1947 and 1948, where it appears as a small open circle labelled simply "Souterrain" in the south-west part of the rath.

The surviving remains sit in the north-west quadrant of the ringfort and include the upper courses of the northern side-wall, those two in-situ lintels at the western end of what may once have been a rectangular chamber, and a possible creep or recess extending southward from the eastern end of the depression. A creep, in this context, is a low, narrow connecting passage between chambers, designed to slow intruders or control airflow. This one measures approximately two metres in length and one metre in width. The partial collapse makes any firm interpretation difficult, and the archaeological record is careful to describe features as possible rather than certain, which is itself a useful reminder of how much early medieval underground architecture survives only in fragments, readable more as absences in the ground than as standing structures.