The site known as Lisgortrahoon contains a souterrain, an underground stone-lined tunnel or chamber typically associated with early medieval settlement, built into the northern sector of a rath that still rises, quietly and without announcement, from the surrounding fields.

The rath itself is subcircular, measuring roughly 30 metres east to west, and survives in fair condition. A rath is a ringfort, a type of enclosed farmstead common across Ireland during the early medieval period, generally defined by an earthen bank and an outer ditch. Here, the enclosing bank is formed from earth and stone, and traces of stone-facing remain visible along its inner face at the north-east. The external fosse, the ditch running outside the bank, survives only from the north-west around to the north, the rest having been gradually absorbed or obscured. Later field walls have been laid directly over the enclosing element along the southern and north-western arc, the kind of incremental agricultural overwriting that makes these sites easy to overlook. McCaffrey noted the site in 1952, cataloguing it among a wider survey of the area's monuments.

The souterrain, recorded separately under its own reference, sits in the northern part of the interior. Souterrains were often used for cold storage or as places of refuge, and their presence within a rath is not unusual, though it always adds a layer of purposeful concealment to what might otherwise read as a simple agricultural enclosure. The slight rise on which the whole structure sits, modest as it is, would have been enough to offer some drainage and visibility across the surrounding undulating ground.