But when vegetation clearance ahead of tree planting broke the surface at Ballynacourty, what emerged was a scatter of burnt stones and charcoal-rich soil, the quiet signature of a fulacht fiadh, or burnt mound. These features are among the most common prehistoric monuments in Ireland, yet they remain poorly understood. The working theory is that they served as cooking sites, where stones were heated in a fire and then dropped into a water-filled trough to bring it to the boil, with the cracked and shattered stones discarded into a characteristic horseshoe or kidney-shaped mound nearby.

The Ballynacourty example sits in bogland, covered by rough moorgrass and gorse, immediately east of a south-flowing river. That riverside position is entirely typical. Burnt mounds almost always appear close to a water source, which would have been essential for whatever process was being carried out, whether cooking, bathing, textile preparation, or something else entirely. The mound itself is modest, measuring roughly eight metres north to south and six metres east to west, and the surrounding bog has done the work of preserving it, sealing the burnt material beneath layers of peat and vegetation until groundwork for forestry brought it briefly to light.