It is a fulacht fia, a type of prehistoric cooking site found in their hundreds across Ireland, typically recognised by their distinctive horseshoe-shaped spreads of burnt and shattered stone. The basic principle was straightforward: a trough, often timber-lined, was filled with water, and stones heated in a nearby fire were dropped in to bring the water to boiling point. Repeated heating and rapid cooling eventually caused the stones to fragment and blacken, and over generations of use the discarded material accumulated into the characteristic mounds that survive today.

The site at Coolroe More is described as heavily overgrown, its mound of burnt material now merging with the wet, soft ground around it. Marshy locations are typical for fulachtaí fia, which required a reliable and accessible water source. Most examples in Ireland date to the Bronze Age, broadly spanning from around 2000 BC to 500 BC, though some sites show evidence of use across multiple periods. The sheer number of these sites identified across the Irish landscape suggests they were a routine feature of prehistoric life rather than anything ceremonial or exceptional, though debates continue about whether they served exclusively for cooking, or also for purposes such as textile processing or bathing.