Beneath the ground, a souterrain, an artificially constructed underground passage of the kind used in early medieval Ireland for storage or refuge, ran eastward from a circular hut and was said to extend all the way to a large cairn some fifty metres away. That distance, if accurate, would make it a notably ambitious piece of underground construction. Today, almost all of that above-ground evidence has gone.

The site at Liscunneendeen, or Lios Coinín Doinn in Irish, belongs to a class known as a univallate rath, meaning a roughly circular enclosure defined by a single earthen bank or rampart. These were the farmsteads of early Christian Ireland, typically dating from somewhere between the sixth and tenth centuries, though the type persisted longer in some areas. When early Ordnance Survey fieldworkers visited, they recorded a circular stone ruin inside the enclosure measuring twelve feet across and five feet high, which is thought to correspond to the hut from which the souterrain led. That structure no longer exists. What remains visible in the interior are two irregular depressions, each about three-quarters of a metre deep, likely marking where the underground passage has partially collapsed. The cairn to the north-east, composed of a mixture of earth and stone and measuring roughly eleven metres by eight metres, still stands at one and a half metres in height, and if the souterrain truly once connected the hut to this mound, the relationship between the two features raises questions that have not been fully answered. J. Cuppage documented the complex as part of the Dingle Peninsula Archaeological Survey published in 1986, and it is largely from that work that the details of the site are known.