From the air, the pasture revealed what is known as a cropmark, a phenomenon where buried features influence how grass or crops grow above them, causing subtle variations in colour and height that are invisible at ground level but readable from above. What the photograph shows is a D-shaped enclosure, its flat western side abutting a linear feature, the whole impression suggesting an organised, enclosed space that may once have served a domestic or agricultural purpose. By the time anyone walked the ground to look for it in 2000, there was nothing to see at all.

Enclosures of this kind are relatively common in the Irish archaeological record, often associated with early medieval settlement. A D-shaped or roughly circular enclosure surrounding a dwelling or farmstead, sometimes called a rath or ringfort, could be constructed from earthen banks and ditches, materials that over centuries of ploughing and grazing can be reduced to nothing detectable underfoot. The linear feature adjoining the enclosure's western side might represent a field boundary, a roadway, or some other organising element of an earlier landscape. Without excavation, none of that can be stated with certainty for Knockavurra Glebe, and the aerial photograph remains the sole record of the site's existence.