It measures roughly 8.3 metres long and 4.3 metres wide, oriented north to south, and beneath the turf lies a spread of burnt material that marks it as a fulacht fia, one of the most commonly encountered yet persistently mysterious monument types in the Irish landscape.

Fulachtaí fia are horseshoe-shaped or oval mounds composed largely of fire-cracked stone, charcoal, and scorched earth, the accumulated debris of repeated high-temperature activity. The leading theory holds that they functioned as cooking sites, probably during the Bronze Age, where water held in a timber- or stone-lined trough was heated by dropping fire-heated stones into it. Experimental archaeology has shown the method works efficiently, bringing a large volume of water to a boil in under half an hour. Their consistent proximity to water, as at Coolanarney where the mound lies on the east bank of a stream, fits this interpretation neatly. Some researchers have proposed additional uses, including textile processing or even bathing, though cooking remains the most widely accepted explanation. Ireland has thousands of recorded examples, making them a routine feature of the Bronze Age countryside, yet the precise social context of who used them, and when, and why they accumulated such quantities of discarded stone rather than clearing the debris, is still debated.