That absence is precisely the point. The site exists most fully on paper, recorded on the 1903 to 1904 edition of the Ordnance Survey six-inch map as a sweeping arc of bank running from the north-west, around to the north, and out to the east-south-east, with an overall diameter of roughly 32 metres. Even then, its western edge had already been cut through by a field boundary. By the time a surveyor visited in 1975, the earthwork had been levelled entirely into the improved pasture that now covers the slope.

Enclosures of this kind, roughly circular or oval earthen banks enclosing a defined interior space, are among the most common archaeological features in the Irish landscape, though their dates and functions vary considerably. Some served as farmsteads, others as ceremonial or burial sites. What happened at Knockkelly is not recorded, but the fate of the monument is familiar enough: as agricultural land was drained, cleared, and reseeded across the twentieth century, thousands of low earthworks like this one were quietly absorbed back into the ground. The field boundary that clipped the western arc suggests the process had already begun before the early twentieth-century mapping, meaning the enclosure was being gradually consumed across at least two distinct periods of agricultural change.