It exists, at least to the modern eye, only from the air, betrayed by the way crops grow differently over buried features, producing subtle variations in colour and height that aerial photography can read like faint handwriting. This kind of mark, known as a cropmark, forms when soil disturbance from old ditches or banks retains moisture differently from the surrounding ground, causing the vegetation above it to ripen or wither at a different rate. What the photographs reveal at Barrowmount is a concentric enclosure, a site consisting of two roughly circular boundaries, one set inside the other, with a gap of around thirty metres between them.

The overall diameter of the feature runs to approximately 140 metres, with the inner enclosure measuring somewhere between 50 and 60 metres across. Concentric enclosures of this kind are found across Ireland, and while their precise functions varied, they are generally associated with the early medieval period or earlier, sometimes serving as high-status settlements, ceremonial spaces, or boundaries marking out a place of particular social or ritual significance. The double-ring arrangement, with that wide annular band between the two circuits, was not a casual layout, and such sites often indicate a deliberate and meaningful use of space. The Barrowmount example came to light through aerial survey work, with photographs taken on two separate occasions in July and August 1996 capturing the feature clearly enough to record its form and dimensions.