But the depression sitting inside a ringfort at Calliaghstown carries a particular kind of quiet weight, because it may be all that remains visible of a souterrain, an underground passage or chamber built, typically in early medieval Ireland, for storage, refuge, or both.

The ringfort itself occupies a small but distinct rise in the landscape, set against gently rolling grassland. Ringforts, which are circular enclosures defined by earthen banks or stone walls, were the most common form of rural settlement in early medieval Ireland, and many contained souterrains dug beneath or alongside the main living area. The one at Calliaghstown has left behind a depression measuring twelve metres in length, with a top width of 4.3 metres narrowing to two metres at the base, a profile consistent with the gradual collapse of a roofed underground structure whose covering has long since given way. Whether the passage beneath survives in any form is another question entirely.