There is no earthwork to see, no raised bank or sunken ditch. The enclosure reveals itself only from above, and only under the right conditions: a dry summer drawing moisture unevenly from the soil, causing the grass or crop overhead to grow at slightly different rates depending on what lies beneath. This kind of ghost feature is known as a cropmark, and it is through one, spotted on satellite imagery, that this small ring-ditch at Grange came to light.

A ring-ditch is typically the buried remnant of a circular ditch, often all that survives of a prehistoric burial mound after centuries of ploughing have levelled the upstanding earthwork above it. They appear across Ireland in considerable numbers, many of them known only because aerial photography and satellite imagery have made it possible to read patterns in the landscape that ground-level observation simply cannot catch. This particular example was identified and reported by Simon Dowling, who noticed the circular mark on Google Earth imagery dated 14 July 2018. The site sits on what amounts to a small island, bounded on the east by the main channel of the River Barrow and on the west by an offshoot of the same river, with the surrounding land in tillage. That combination of riverside location and long agricultural use is precisely the kind of context in which buried monuments tend to survive below the plough-line while disappearing entirely from the surface above it.