The feature was picked out as a cropmark, a phenomenon where buried walls, ditches, or other sub-surface structures cause differential growth in crops above them, producing patterns that become visible from altitude. Aerial photographs taken on 14 July 1970, catalogued under the Cambridge University Collection of Aerial Photography reference CUCAP BDI005 and BDI006, captured what appears to be a rectangular enclosure in tillage ground at Lyrath.

The interpretation is tentative, and that uncertainty is part of what makes the site interesting. Analysts have noted that the cropmark could equally represent a fragment of a larger co-axial field system, a type of organised landscape division in which parallel boundaries run in the same general orientation across a stretch of ground, in this case roughly north-east to south-west. The surrounding area adds texture to the puzzle. A second rectilinear cropmark enclosure sits immediately to the south, and approximately 100 metres to the south-west lies a ringfort, the circular or oval enclosed settlement that was the most common form of rural farmstead in early medieval Ireland. A curving trackway, also identified as a cropmark, runs roughly north-east to south-west to the north-west of the ringfort. Taken together, these features suggest a landscape that was organised, inhabited, and subdivided over a considerable period, though precisely when, and by whom, the enclosure at Lyrath was laid out remains an open question.