It shows itself only from the air, as a cropmark, the faint signature left in growing vegetation when buried earthworks alter how moisture and nutrients move through the soil above them. Centuries of ploughing and weathering have flattened whatever once rose above the surface, but the geometry underneath persists.

What the aerial photograph reveals is the plan of a ring barrow, a type of funerary monument typically dating to the Bronze Age, consisting of a circular bank with a ditch, known as a fosse, running along its inner edge rather than the outer. This inward placement of the fosse is one of the features that distinguishes ring barrows from related enclosure types. The example at Ardglare is small, less than twenty metres in diameter, and is known from a single aerial image. Beyond that outline, the site holds its details close.