These features, typically appearing as low horseshoe-shaped mounds of fire-cracked stone, represent a form of ancient communal cooking in which water was heated by dropping hot stones into a trough, sometimes lined with wood or stone. The method was efficient enough to bring water to a boil within minutes, and experiments have shown it could cook large joints of meat in a matter of hours. Ireland has more recorded fulachta fiadh than almost anywhere else in Europe, and Kilkenny has its share, scattered across townlands that have long since absorbed them into the ordinary fabric of farmland.

The site at Firgrove belongs to this widespread but still not fully understood tradition. Bronze Age in origin, these monuments are generally dated to somewhere between 1500 and 500 BC, though many were used and reused across long periods. The mounds survive because burnt and shattered stone, though useless for further cooking, was simply piled to one side of the trough after each use, accumulating over time into the distinctive crescent shape that fieldworkers still identify today. Beyond its location in the Firgrove townland, the specific details of this particular site remain sparse, and the fuller record has not yet been made publicly available.