At Coolroe in County Kilkenny, one such site sits quietly in the landscape, a low horseshoe-shaped mound of burnt and shattered stone that most people would walk past without a second glance. That unremarkable appearance, however, conceals something genuinely curious: these mounds represent the remains of Bronze Age cooking sites, or possibly bathing facilities, where stones were heated in fire and dropped into water-filled troughs to bring the liquid rapidly to the boil. The cracked, heat-spent stones were then discarded to the side, building up over repeated use into the distinctive mounds that survive today.

The fulacht fia tradition is broadly dated to the Bronze Age, roughly 1500 to 500 BC, though examples have been found from earlier and later periods. Ireland has more of them than anywhere else in Europe, yet their precise function remains a matter of debate among archaeologists. Cooking is the most widely accepted explanation, supported by experiments showing that the method works efficiently for boiling large joints of meat. Other proposals include their use as sweat houses, textile dyeing vats, or brewing vessels. The Coolroe example, located in a county that contains numerous such monuments across its varied terrain of river valleys and farmland, belongs to this long and still-contested tradition.