Cattle graze across it, the ground is level, and there is no visible earthwork, no mound, no ditch. Yet the 1842 Ordnance Survey six-inch map tells a different story, showing a hachured rectangular enclosure, roughly 30 metres east-west and 25 metres north-south, its south-western edge already clipped by a roadway even at the time of surveying. The road that cut into it may well have hastened its end.

By 1934, when a researcher named Bowman documented it, the structure was already gone from the ground. Bowman recorded it as a levelled square fort, with sides of approximately 27 yards, situated on land belonging to a Mrs. Sexton. The term "fort" here is the older vernacular use, applied loosely to any enclosed ringfort-type site rather than a military installation. Ringforts, which are enclosed farmsteads dating broadly from the early medieval period, were once extraordinarily common across Ireland, and a great many were lost to agricultural improvement over the eighteenth and nineteenth centuries. This one in Glen appears to have been among them, surviving on paper long after it had disappeared from the earth beneath it.