The one at Cunnagher in County Mayo is a quiet example of a type that has puzzled researchers for generations. A fulacht fia typically appears as a horseshoe-shaped or kidney-shaped mound of fire-cracked stones, usually found close to a stream or boggy ground. The prevailing theory holds that they were used for cooking, with water heated by dropping stones that had been fired in a nearby hearth directly into a trough, bringing the liquid rapidly to a boil. Bronze Age in date for the most part, though some examples span a wider range, they represent a technology that was practical, repeatable, and widespread enough to have left marks on the landscape from one end of the island to the other.

The Cunnagher site sits within a county that has no shortage of prehistoric remains, from megalithic tombs on the Céide Fields plateau to the ritual landscapes around Lough Carra. Mayo's boglands have preserved organic material extraordinarily well over the millennia, which is part of why fulachtaí fia survive here in recognisable form at all. The waterlogged conditions that make upland Mayo difficult farming country are precisely the conditions that slow the decay of ancient timber troughs and charred stone deposits. Beyond its location and classification, the specific details of the Cunnagher fulacht, its dimensions, its state of preservation, and any associated features, remain to be fully documented in the public record.