This is a fulacht fia, a type of prehistoric cooking place found in extraordinary numbers across Ireland, typically identified by the distinctive mound of shattered, heat-fractured stone that accumulates when heated rocks are repeatedly plunged into water to bring it to the boil. The method is indirect; the stone does the work that a direct flame cannot do so reliably. The site at Killeen sits to the east of a spring, which is entirely typical. Water is the functional heart of any fulacht fia, and the proximity of a natural source was almost certainly what drew people to this particular spot in the first place.

What makes the Killeen example quietly interesting is not its solitude but its company. Two further fulachta fiadh lie close by to the south, forming a loose cluster in the same landscape. Whether they represent repeated use of a favoured area over generations, or near-contemporary activity by the same community, is not something the surface evidence can settle. The spread of burnt material recorded here is the characteristic signature of the type, the blackened, charcoal-flecked debris that survives in damp, low-lying ground long after any wooden trough or organic structure has disappeared entirely. Cork is among the richest counties in Ireland for these sites, and mid Cork in particular has yielded a considerable concentration of them.