It exists, effectively, only from the air. A roughly circular feature approximately forty metres in diameter, it announced itself to the modern world not through excavation or documentary record but through a single aerial photograph taken on 16 July 1971, when the conditions of a particular summer day made the buried outline visible as a cropmark.

Cropmarks form when buried features alter how vegetation grows above them. Ditches and pits, filled over centuries with softer sediment, tend to retain more moisture, encouraging crops or grasses to grow taller and stay greener; foundations and compacted surfaces have the opposite effect. From ground level, these differences are imperceptible, but from altitude, especially in dry conditions when stress on vegetation is highest, patterns emerge with sometimes startling clarity. The Clintstown enclosure is situated well above the flood plain of the Nuenna river, which runs about 260 metres to the south, a positioning that would have made the slightly elevated ground attractive for settlement or enclosure at some point in the prehistoric or early medieval period. It does not sit in isolation. A second enclosure lies roughly 140 metres to the north-north-west, and a ring-ditch, a type of circular earthwork often associated with prehistoric funerary or ritual activity, sits about 60 metres to the north. All three were identified from the same kind of aerial evidence, suggesting that this stretch of the valley once held a concentration of activity now entirely invisible beneath the grass.