Nearly fifty metres across, it was not identified by ground survey but spotted from the air, its outline legible only at altitude as a broad grassed-over ring in the landscape. A cashel is a type of ringfort built from drystone rather than earthen banks, and this one at Caherhenryhoe retains enough of its original fabric to show external wall-facing along its western to north-north-western arc, where the stonework has tumbled but not entirely dispersed. Elsewhere the wall has merged with the ground, becoming little more than a grassy swell.

The interior adds a further layer of ambiguity. Crossing it are several low, irregular stony banks running roughly north to south; these may belong to a later period than the cashel itself, perhaps field divisions or structural remains of a different use, though the question remains open. More intriguing still is a possible souterrain in the southern sector. A souterrain is an underground stone-lined passage or chamber, commonly associated with early medieval settlements in Ireland and thought to have served as storage space, a refuge, or both. Whether the one at Caherhenryhoe is genuinely connected to the cashel, or represents a separate feature entirely, has not been resolved. What the site offers, in other words, is less a set of answers than a series of overlapping questions pressed into a hillside in County Galway.