A photograph taken in July 1996 captured cropmarks, the faint differential growth in vegetation that betrays buried features beneath ploughed soil, revealing three conjoined enclosures arranged along the southern edge of a larger enclosure that has long since been levelled by cultivation. Two of the three are curvilinear in shape; the third is rectilinear. Each is defined by a fosse, a defensive or boundary ditch, and together they most likely represent the working fields attached to a nearby ringfort.

Ringforts, the circular enclosed farmsteads that are among the most common early medieval monuments in Ireland, were rarely isolated features. They sat within a working agricultural landscape, and the fields, paddocks, and enclosures around them were as much a part of the settlement as the dwelling inside the bank and ditch. What the aerial photograph at Dunbell Big preserves is precisely this outer layer, the organisation of land around a homestead, in a form no longer visible on the ground. The parent enclosure to the north has been plough-levelled entirely; these three subsidiary enclosures survive only as shadows in a crop.