What lies beneath the turf is the remains of a fulacht fia, a type of prehistoric cooking site found in considerable numbers across Ireland, typically dating from the Bronze Age. The name, loosely translated from the Irish, is associated with cooking pits used by hunters or travelling bands, and the physical signature is almost always the same: a mound of fire-cracked stone and charcoal-blackened earth, built up over repeated use.

The mechanics of these sites are straightforward but ingenious. A trough, usually cut into the ground and sometimes timber-lined, was filled with water. Stones were heated in a fire nearby and dropped into the trough until the water boiled, allowing meat to be cooked. The cracked and spent stones were then discarded to the side, gradually forming the characteristic horseshoe-shaped mound. At Aghaville, the presence of streams to the south and east of the site points to exactly the kind of setting these features consistently occupy; proximity to a reliable water source was not incidental but essential to the whole process. The location in low-lying, recently reclaimed pasture is also typical, since fulachtaí fia tend to cluster in wet or marginal ground, which is one reason so many survived undisturbed for millennia beneath bog or rough grazing land.