"Flat cemetery" is not a descriptive accident; it marks a site where a prehistoric mound, clearly visible on the Ordnance Survey's six-inch map of 1838, had by the time of the 1908 revision been levelled to nothing, with field fences built directly over what remained.

The site's significance only became apparent by accident. In 1994, the bulldozing of those same field fences disturbed a rectangular stone-lined cist, a type of box-shaped burial chamber formed from upright slabs, which prompted investigation by the National Museum of Ireland. Subsequent excavations led by Barra Ó Donnabháin between 1994 and 1995 revealed that the flattened field concealed considerably more: multiple cists and pits, a surviving portion of the original mound, and three ring-ditches. Ring-ditches are the circular drainage channels that once surrounded round mounds or barrows; they frequently survive as the last trace of burial monuments whose earthen cores have long since been ploughed or scraped away. A poorly defined circular enclosure of roughly 25 metres in diameter, marked by a slight scarp still forming about a quarter of a circle, had been noted during a field inspection in 1989, though its full extent was not understood until the excavations brought the buried features to light. The picture that emerged was of a prehistoric funerary landscape quietly persisting beneath farmland that had done its best to erase it over the course of a century and a half.