It is easy to overlook, and that is precisely what makes it worth knowing about. Beneath the turf lies a spread of burnt material roughly seven metres by seven metres wide, the physical remains of a fulacht fia, one of the most common yet least understood monument types in the Irish landscape.

A fulacht fia is essentially a prehistoric cooking site, though the term covers a range of possible uses that archaeologists still debate. The typical arrangement involves a trough dug into the ground, a hearth for heating stones, and a mound of those same stones discarded after use, cracked and fire-shattered from repeated immersion in water. The burnt and fragmented stone accumulates over time into the spreads and horseshoe-shaped mounds that survive in their thousands across Ireland, most often in low-lying, wet ground beside streams or springs. The boggy setting at Lismeelcunnin is entirely characteristic; water was a functional necessity, and the poorly drained ground that made such sites awkward for later agriculture is precisely what helped preserve them. They date broadly to the Bronze Age, roughly 1500 to 500 BC, though some sites show evidence of use across longer periods.