In a field at Oldgrange in County Kildare, there is nothing obvious to see. No earthwork rises from the soil, no stone marks the ground. What exists here is visible only from the air, and only under the right conditions: the ghostly outlines of ancient enclosures, betrayed by the way crops grow differently above disturbed or compacted soil. These are cropmarks, and they are among the quieter ways the past makes itself known.

The site came to light on 13 July 1990, when Dr. Gillian Barrett photographed the area as part of an aerial photographic survey. The resulting image, catalogue reference GB90.BC.09, reveals two conjoined curvilinear enclosures, their rounded forms pressed together. Between them on the southern side sits a smaller lunate enclosure, crescent-shaped, acting as a kind of connecting chamber. A similar lunate feature borders the northern side of the western enclosure. Beyond the enclosures themselves, faint traces of short linear fosses, that is, ditches, extend outward from the main forms, suggesting that whatever activity took place here was not confined to the enclosures alone. This pattern is consistent with an associated field system, hinting at organised land use rather than a single isolated structure. The date of the site's original use is not known from the cropmarks alone, but conjoined curvilinear enclosures of this type are a recurring feature of the Irish landscape and are often associated with prehistoric or early medieval settlement.