What turned up during ploughing was a spread of burnt stones, the kind of archaeological feature that speaks of repeated, purposeful fire without leaving any visible mark on the landscape above ground.

Burnt stone spreads of this kind are closely related to fulachta fiadh, a type of site found widely across Ireland and generally associated with Bronze Age activity. The typical interpretation involves heating stones in a fire, dropping them into a water-filled trough to bring it to the boil, and using the resulting heat for cooking or possibly other purposes such as bathing or textile working. The stones crack and shatter with repeated heating and cooling, and over time accumulate into the characteristic spreads and mounds that survive at many Irish sites. At Kilgarvan, Paddy O'Donovan recorded the discovery in 1987, when ploughing brought the burnt material to light. By that point, no surface trace remained to indicate anything was there at all.