It is not much to look at from above, but that gap in the ground is the only visible sign of a souterrain, an underground passage built from drystone walling and long since sealed off from the world. Local tradition holds that the structure was deliberately closed up within living memory, referred to simply as a cave, which suggests people in the area were aware of it as something navigable, even if they did not know exactly what it was.

A souterrain is an underground passage or chamber, typically associated with early medieval settlement in Ireland, often used for storage or as a refuge. This one sits within the north-western quadrant of a ringfort, the remains of a circular enclosure that would once have been a farmstead of some kind. The souterrain itself was examined in 1979 and found to extend roughly 4.3 metres in a south-westerly direction, with a width of about 1.6 metres and a ceiling height of between 0.4 and 0.6 metres, low enough that crawling would have been the only way through. The walls are described as poorly constructed drystone work, stones laid without mortar, which is not unusual for this kind of structure. At the south-western end of the north-western wall there is a small opening that appears to lead into a further passage or chamber, though what lies beyond it has been made inaccessible partly by collapse and partly by the activities of badgers, who have found the underground network rather more useful than any archaeologist would prefer.

The surrounding land is open pasture with wide views to the south-east, and a pond sits roughly eighty metres to the south. Entry into the souterrain is not possible, and there is nothing here that invites close inspection so much as a certain quiet attention to what the landscape conceals just beneath its surface.