What was found inside, or why they were closed up again, is not recorded. What remains visible on the surface are two shallow depressions, each roughly two metres across and a metre deep, sitting in the interior of the fort and near its eastern bank. These hollows are likely the collapsed roofs of further chambers that nobody has yet excavated.

A souterrain is a type of underground passage or chamber built from stone, typically associated with early medieval settlement in Ireland, roughly the sixth to twelfth centuries. They are commonly found within ringforts, the circular enclosed farmsteads that dot the Irish countryside in their thousands, and are thought to have served as storage spaces, refuges, or both. The Teerelton example sits within one such ringfort, and the local knowledge that chambers once existed here, combined with the sunken ground still visible today, suggests a more extensive underground structure than has ever been formally recorded. The fact that the known chambers were filled in rather than studied means whatever they contained, architecturally or archaeologically, is essentially lost to the record.