What was found there, a mound of burnt stone mixed with charcoal-flecked soil, is the physical fingerprint of a fulacht fia, one of the most common yet quietly puzzling monument types in the Irish archaeological record. These sites, found in their thousands across Ireland, are thought to represent ancient outdoor cooking places, typically involving a trough of water brought to the boil by dropping fire-heated stones into it. The stones crack and splinter with repeated heating and cooling, and over time the discarded fragments accumulate into the characteristic horseshoe-shaped mounds that survive to this day.

The Killincarrig site first came to attention during test excavations carried out by Margaret Gowen in 1992. A subsequent, more thorough excavation of the area, designated Area 1, was led by Alan Hayden in 1993, and it was this work that confirmed the presence of a fulacht fia beneath the surface. The excavation did not, however, expose the full extent of the monument. How far the remains continue underground remains an open question, which means that part of this prehistoric site is still unexamined, its full shape and scale unknown.