A souterrain is an underground stone-lined passage or chamber, typically associated with early medieval settlement in Ireland, often thought to have served as a place of refuge, storage, or both. This one was once substantial enough to be recorded on Ordnance Survey maps from 1841 to 1842, where the cartographers noted a "cave" within the interior of a circular enclosure. By the time the maps were revised for the 1914 to 1915 edition, the feature was still being marked. Today, no surface trace survives.

What makes this site quietly strange is the gap between its cartographic persistence and its physical disappearance. For the better part of a century, surveyors thought it worth recording, and the label "cave" on the earlier Ordnance Survey sheet suggests the underground element was either visible or locally well-known at the time. The enclosure itself, a circular earthwork of the kind commonly associated with early medieval farmsteads in Ireland, sits in the same field as a second enclosure to its north-west. C. Toal's North Kerry Archaeological Survey, published in 1995, documented what remained of the record, drawing on both the map evidence and fieldwork. By that point, the ground had already given nothing away.