It came to light not through any planned excavation but through demolition: when an earthwork enclosure on a small ridge was destroyed in 1933, the work broke through into a souterrain, a type of stone-lined underground passage and chamber used in early medieval Ireland, typically for storage or refuge. The discovery was reported to the Gardaí in Kells, who in turn corresponded with the National Museum of Ireland, describing what they found in plain, careful terms.

The structure they entered was substantial. A beehive chamber, meaning a roughly corbelled, dome-shaped room built without mortar, measured approximately 3.65 metres wide and 1.8 metres high. Leading away from it was a passage some 14 metres long. Both dimensions suggest a well-built, deliberate construction rather than a simple hollow. Among the objects recovered were what was described as an axehead and a fragment of a bone comb, modest finds but the kind that point to actual use rather than abandonment. Once the chamber had been examined, it was closed again. By 1968, there was no visible trace of it at the surface, and the earthwork enclosure within which it had originally sat was long gone. The ridge on which all of this once stood, a low feature running roughly northwest to southeast for about 150 metres, survives only in the historical record.