A promontory fort works by letting the sea do most of the defensive work, with a stretch of open Atlantic on three sides and a constructed barrier, typically a bank and ditch, cutting across the narrow landward approach. The result is a stronghold built as much from geography as from human labour.

Beyond the classification and the location, the documentary record for this particular site is presently sparse. What can be said with confidence is that coastal promontory forts in Ireland date broadly from the Iron Age, though many were used and adapted across several centuries, and the western seaboard of Mayo contains a notable concentration of them. The clifftop and headland settings that made these places defensible also made them difficult to farm and easy to overlook, which is part of why a number survive at all, their earthworks largely undisturbed by later agriculture.