This is a cropmark, a phenomenon in which the buried remains of walls, ditches, or pits affect how plants take up moisture and nutrients, causing the vegetation above to grow at different rates and produce subtle variations in colour and height. From ground level, there is nothing to see. From the air, the outline becomes legible, a ghost of a ring pressed into the earth.

The enclosure at Cooperhill came to light through aerial imagery captured on 14 July 2018 and viewed on Google Earth. Circular enclosures of this general scale are found across Ireland and can represent a broad range of site types, from early medieval ringforts used as enclosed farmsteads to prehistoric burial monuments or ceremonial sites. Without excavation, it is impossible to say which category this example belongs to, or what period it dates from. The diameter of approximately 45 metres places it within the range commonly associated with ringforts, though that alone is not sufficient to identify it with confidence. The site was recorded by Caimin O'Brien on the basis of details provided by Jean-Charles Caillère, and uploaded in September 2019.