At Carheenard in County Galway, a prehistoric or early medieval field system once spread outward from a central enclosure in a pattern that would have been legible to anyone working the land nearby. By the time anyone thought to look carefully, it was already nearly gone.

What survives in the record comes from a single aerial reconnaissance flight in December 1984. Low winter light and the angle of the camera revealed faint traces of field banks radiating outward from a nearby enclosure, the kind of earthwork boundary, typically circular or oval, that was used in early Ireland for settlement, livestock management, or both. Aerial photography of this kind works precisely because shadows fall differently across slight undulations that the eye at ground level cannot distinguish from ordinary uneven ground. Those undulations were enough, just barely, to show that organised agricultural activity had once structured this landscape. The field banks have since been levelled through agricultural clearance, and no visible surface trace now remains at the site.