The raised circular platform, roughly 32 metres across and defined by a scarp face standing some 4.5 metres high, is substantial enough to read clearly in the landscape. But the most telling detail is a large, irregular hollow at the west-south-west of the interior, the tell-tale depression of a collapsed souterrain.

A souterrain is an underground stone-lined passage or chamber, typically associated with early medieval settlement and used for storage, refuge, or both. Here the roof has given way entirely, leaving the hollow as the only visible sign that something once ran beneath the ground. On the north-east slope of the platform, a ramp-like feature partly edged with stones may mark the original entrance to the fort itself, the point where whoever lived here passed daily between the enclosed upper ground and the world outside. Across much of the interior, cultivation ridges roughly three metres wide run on a north-east to south-west axis, evidence that the platform was later pressed into agricultural use, most likely for lazy-bed potato cultivation. Notably, these ridges stop short around the area of the souterrain, suggesting either that the hollow made cultivation impractical there or that the collapse post-dates the ridge-making.