In the gently undulating pasture of Cloonagleavragh, County Sligo, that is precisely the situation. The Ordnance Survey's six-inch map of 1838 records a roughly circular ring of trees about twenty-five metres in diameter, sitting within a small square field of around thirty metres each side. By the 1913 edition, the feature had disappeared from the cartographic record entirely, and today there are no remains visible at ground level.

What makes the site more than a cartographic curiosity is the souterrain at its centre. A souterrain is an underground stone-lined passage or chamber, typically associated with early medieval settlement, used for storage or as a place of refuge. The 1838 map marked this one simply as "Cave". The combination of a circular tree-ring and a souterrain at its core is suggestive: ringforts, the enclosed farmsteads of early medieval Ireland, frequently incorporated souterrains within their interiors, and the circular arrangement of trees may represent the ghost of an earthen bank that has since been levelled. Whether the bank was deliberately removed between the two survey dates, or simply eroded and spread over time, is not recorded. What remains is a trace on old paper and a hollow in the ground, hinting at a domestic life that otherwise left no mark on the landscape.