A low mound of burnt and shattered stone, measuring roughly eleven metres from north to south and eleven and a half east to west, marks the site of a fulacht fia, one of the most common yet quietly puzzling monument types in the Irish archaeological record. A fulacht fia is a Bronze Age cooking place, typically consisting of a trough dug into the ground beside a water source, a hearth for heating stones, and a mound of the thermally cracked stone that accumulated over repeated use. Thousands of them survive across Ireland, and yet the details of how and why they were used, whether for cooking meat, brewing, bathing, or some combination, remain a matter of ongoing discussion among archaeologists.

The Garryadeen example followed a fate common to many such monuments in the twentieth century, when agricultural improvement schemes, drainage works, and general land clearance removed features that had survived for perhaps three thousand years. This particular mound was levelled around 1974, leaving only the low spread of burnt material that can still be detected in the field. Before that intervention, it would have presented as a characteristic horseshoe-shaped or kidney-shaped spread of dark, fire-cracked stone and charcoal-stained earth, the accumulated debris of a site used repeatedly over a long period.