Cut into the outer face of the bank, just east of the southern entrance, is a narrow opening that leads into an L-shaped souterrain, an underground passage built from dry-laid stone without mortar, of the kind constructed throughout early medieval Ireland for storage or refuge. The passage runs northwards for three and a half metres before turning east for a further two and a quarter metres. It is only about seventy centimetres wide and just over a metre high, roofed by seven flat slabs laid across the top. One of those slabs, at the eastern end, has collapsed inward, and the resulting hollow may be what accounts for one of the two shallow depressions visible in the interior of the fort above ground.

The rath itself is a univallate ringfort, meaning it has a single enclosing bank rather than the multiple concentric banks associated with higher-status sites. Its internal diameter is thirteen metres, and the bank rises one metre on its outer face, dropping to about sixty centimetres on the inside. It sits on a south-east facing slope, a position that would have given its occupants a clear view over Dingle Harbour below. J. Cuppage documented the site in the 1986 Dingle Peninsula archaeological survey, "Corca Dhuibhne," which catalogued the extraordinary concentration of early medieval and prehistoric remains across this part of Kerry. By that point the southern entrance had already been widened at some recent stage, an alteration that affects what would otherwise have been the most legible original feature of the enclosure.