No earthwork rises from the ground, no stone marks the spot; the only way to read this place is from the air, where a difference in soil moisture or crop growth betrays the outline of a rectilinear enclosure measuring roughly 40 to 50 metres across. These ghostly patterns, known as cropmarks, appear when buried features such as ditches or banks cause the vegetation above them to grow differently from the surrounding soil, becoming visible in aerial photographs under the right seasonal conditions. It is a quiet kind of archaeology, legible only to the camera and the trained eye.

The enclosure at Borrisbeg was identified from aerial photographs taken in July 2000. Its roughly rectangular outline is defined by what appear to be two fosses, that is, ditches dug to demarcate or defend an enclosed space. Two existing field boundaries, one running roughly east-northeast to west-southwest and another running north-northwest to south-southeast, follow the lines of the enclosure so closely that the older buried feature and the later field divisions appear to share the same alignment, suggesting the modern landscape has been quietly shaped by something much older beneath it. Further cropmarks hint at associated field boundaries extending outward from the enclosure's northeast angle, one running northwest for approximately 30 metres before turning southwest for around 150 metres. A separate curvilinear cropmark lies roughly 180 metres to the southeast. Together these fragments suggest a small enclosed settlement or farmstead, its precise date and function still uncertain, embedded in a wider pattern of land use that has long since been ploughed smooth.