The one at Coolavally in County Mayo is a locally recorded example of this widespread but still not fully understood type of site. Known in Irish archaeology as "fulachtaí fia" (singular: fulacht fia), these features typically consist of a horseshoe-shaped or spread mound of heat-shattered stone and charcoal-rich soil, usually positioned close to a water source, and dating most commonly to the Bronze Age, roughly 2000 to 500 BC.

The purpose of burnt mounds has been debated for generations. The most widely accepted interpretation is that they represent cooking sites, where stones were heated in a fire and then dropped into a water-filled trough to bring it to the boil, a method practical enough in a world without metal vessels that could sit directly over a flame. Other theories propose uses ranging from communal bathing and textile processing to brewing. Whatever their precise function, the sheer number of these sites across Ireland, running into the thousands, suggests they were a routine and repeated part of life rather than anything ceremonial or rare. The example at Coolavally adds another data point to that distribution across the boggy, water-rich landscape of Mayo, where conditions for both the original activity and the long-term survival of such mounds tend to be favourable.