To a passing eye it might register as nothing more than a slight rise in the field, but it is in fact the remains of a fulacht fia, one of the most common prehistoric monument types in Ireland and one of the least understood.

A fulacht fia is generally interpreted as a Bronze Age cooking site, typically consisting of a horseshoe-shaped mound of burnt and shattered stone surrounding a trough that would have been filled with water. Stones were heated in a fire and dropped into the trough to bring the water to a boil, a method capable of cooking meat efficiently. Over repeated use, the spent, fractured stones accumulated beside the trough, forming the distinctive mound that survives at sites like this one. The Clyderragh example is roughly circular rather than horseshoe-shaped, measuring approximately 10.6 metres north to south and 13.8 metres east to west, making it a reasonably substantial example of its type. The mound material is the accumulated debris of that long-repeated process, burnt stone discarded after each use over what may have been generations.