At certain times of year, when crops grow unevenly over buried foundations or disturbed soil, a near-perfect circle appears from above, twenty metres across, faint but legible to anyone looking at the right altitude and the right moment. This is a cropmark enclosure, a site that exists less as a physical presence than as a seasonal signal, visible only because whatever lies beneath the surface affects how vegetation grows above it.

The site came to attention in June 2018, when researcher Simon Dowling spotted the circular cropmark on Google Earth Pro using satellite imagery dated the 28th of June that year. Cropmarks of this kind typically indicate the buried remains of a ringfort or similar enclosed settlement, structures that were built across Ireland from the early medieval period onward and often consisted of an earthen bank and ditch surrounding a domestic space. The circle at Ballyconra measures roughly twenty metres in diameter, which is modest even by ringfort standards, where sizes can range considerably. One detail adds a small biographical note to the site: a large tree or area of scrub is growing in the interior, slightly south of centre, its roots presumably threading down through whatever archaeology remains below.