In a field near Levitstown in County Kildare, something circular lies buried just beneath the surface, invisible to anyone walking past but legible from the air as a faint ring pressed into the crop. The pattern is a cropmark, a phenomenon where buried ditches or banks cause the plants growing above them to ripen at a different rate from the surrounding soil, tracing the outline of whatever lies below. In this case the ring is roughly twenty metres across, and the shape it describes belongs to a class of monument that is easy to miss on the ground and easy to misread even when noticed.

The feature is interpreted as either a ring-ditch or a ringbarrow, two related but distinct types of prehistoric funerary monument. A ringbarrow typically consists of a low central mound surrounded by a circular ditch, while a ring-ditch may be the eroded remnant of exactly that, the mound long since ploughed away and only the encircling fosse, a term for a ditch dug as part of a boundary or enclosure, surviving as a soil anomaly. Both types are associated with burial and ritual in the Bronze Age, though without excavation it is impossible to say with certainty what lies at the centre of this particular circle, or whether anything survives there at all. The evidence comes from aerial photographs taken as part of the Cambridge University Collection of Aerial Photography, referenced as CUCAP BGN 45 and 49, which captured the cropmark in conditions that made the buried feature briefly readable from above.