By the time anyone walked the ground to look for it in 2013, there was nothing to find.

The photograph was taken by Michael Moore, and whatever he captured from the air has since resisted every effort at verification on foot. Enclosures of this kind, when they do survive, are typically prehistoric or early medieval in origin, their low earthen banks often representing the boundaries of a settlement, a farmstead, or a ritual space. But Calary’s example exists in a curious liminal state: documented, measured, and provisionally described, yet entirely absent at ground level. Whether it was always shallow enough to vanish under bog growth, or whether the aerial image caught a fleeting pattern of soil or vegetation that no longer reads the same way, remains an open question. It has a diameter, a probable orientation, and a date of first observation. It does not, as far as anyone has been able to confirm, have a physical presence.