The Ordnance Survey's first edition six-inch map, produced in 1839, records a D-shaped unenclosed area with the labels 'Ancient Thorn' and 'Site of Grave Yard', two designations that together suggest a place where folk memory and topography had long been entwined. That the tree was already described as ancient by the time the surveyors passed through gives some sense of how far back its association with the dead may reach.

Thorn trees, particularly hawthorns, occupy a distinctive place in Irish tradition. They were frequently left standing at holy wells, fairy forts, and burial grounds, considered either protective or dangerous to disturb, and their presence on early maps often signals that a site carried local significance well beyond its physical dimensions. The area at Coolroe is modest in scale, roughly forty metres on its longer northeast-to-southwest axis and about twelve metres across, but its D-shaped outline and unenclosed character are consistent with informal or early Christian burial grounds found elsewhere in the Irish landscape. By the time of the revised Ordnance Survey maps of 1900 to 1901, the area was still indicated, but the names had been dropped, a quiet erasure that is itself telling. What had been worth recording in 1839 had, within two generations, lost its local identity on the official record, even if the ground itself remained.