The one at Gortavehy is the middle of the three, a horseshoe-shaped mound of burnt and fire-cracked stone measuring roughly nine metres north to south and seven and a half metres east to west, rising to about one and a half metres in height. Its opening, nearly four and a half metres wide, faces west, towards a stream that runs close by.

A fulacht fia is a type of prehistoric cooking monument found in extraordinary numbers across Ireland, with several thousand recorded sites. The typical arrangement involved a timber-lined trough sunk into the ground, filled with water, then heated by dropping fire-heated stones into it until the water boiled. The stones, fractured and blackened by repeated heating and cooling, were raked out and piled to the side over time, which is what forms the distinctive horseshoe or kidney-shaped mound visible today. Most date to the Bronze Age, roughly 1500 to 500 BC, though some are older or later. The proximity to a stream at Gortavehy is entirely characteristic; a reliable water source was essential to the whole operation, and Irish fulachta fia cluster around rivers, streams, and boggy ground with notable consistency. What is less common is finding three of them this close together, spaced at twelve metres and then thirty-six metres apart along what is still, some three thousand years later, soggy upland grazing.