What marks this particular example is how little of it now shows above ground: a shallow circular depression, about one and a half metres across, sitting roughly six metres in from the base of the southern bank. That slight hollow in the earth is, in all likelihood, all a visitor would see.

The ringfort itself is bivallate, meaning it was enclosed not by one but by two concentric earthen banks, a feature generally associated with higher-status settlements in early medieval Ireland. The souterrain was recorded by O'Brien in 1970 and sits in the southern quadrant of this enclosure. Souterrains were typically built by roofing a trench with large stone lintels and then covering the whole structure back over with soil, which is why so many of them survive as faint surface depressions rather than obvious openings. Over centuries of agricultural use, the stonework beneath can shift or collapse, causing the ground above to subside gently, leaving exactly the kind of shallow bowl recorded here at Crooha.