The site at Behagh is tentatively identified as a souterrain, one of the underground stone-lined passages or chambers that early medieval communities in Ireland constructed beneath their settlements, likely for storage, refuge, or both. What makes this particular site quietly compelling is how provisional everything about it remains: the souterrain has not been excavated or confirmed, and its presence is inferred only from a patch of unusually dense growth, roughly four metres east to west and two metres north to south, sitting in the northern sector of a cashel interior.

The cashel itself, a type of dry-stone ringfort enclosure used as a defended farmstead during the early medieval period, is described as poorly preserved, its walls now reduced to the point where the overall form is difficult to read on the ground. It occupies the western end of the ridge summit, a stretch of good mixed pasture and meadowland that would have made it a practical and defensible spot for a farming household in the centuries after the introduction of Christianity to Ireland. The dense vegetation patch is the kind of detail that field surveyors learn to treat with cautious interest: collapsed underground stonework can create subtle dips and disturbances in the soil that favour particular plants, leaving a botanical signature long after the archaeology beneath has been forgotten.