It is described as a cave, but what lies beneath the hillside is something altogether more deliberate: a corbelled and lintelled passage stretching more than 11.4 metres, branching into a series of beehive chambers, each connected by narrow doorways that required anyone passing through to crouch or turn sideways. Corbelling is a technique in which stones are layered so that each course projects slightly inward over the one below, eventually closing into a domed roof without the need for a keystone or mortar. It is one of the oldest building methods in Ireland, associated with prehistoric tombs and early medieval monastic structures alike, and its presence here signals a site that was carefully engineered rather than simply hollowed out.

The layout is unusually complex for a structure of this kind. The original entrance, now blocked, faced WSW, and the main passage slopes downward toward the east. Roughly halfway along, a side passage branches northward into a beehive chamber about two metres in diameter, partly cut directly into the bedrock at its base; this is where the modern entrance was made. Continuing east along the main passage, a narrow doorway, just half a metre wide at its tightest, opens into a second beehive chamber raised slightly above the passage floor. Beyond that, a further sequence of doorways and a short passage leads into a third and final chamber, the tallest of the three at 2.2 metres, with a small air vent positioned above the connecting passage. The precision of those measurements, and the deliberate provision of ventilation, suggest a structure built for sustained use rather than occasional shelter. Whether it served a storage function, a ritual one, or something else entirely, the record does not say.