The one at Cogaula in County Mayo is a representative of this widespread but under-explained type: a low, kidney-shaped or spread mound composed mainly of fire-cracked stone and charcoal-rich soil, sitting close to a water source. They are sometimes called fulacht fiadh in the Irish archaeological tradition, a term loosely associated with outdoor cooking or heating, though what exactly they were used for has been debated for decades. The leading interpretation is that water was boiled by dropping heated stones into a trough, then replenished as the stones cracked and were discarded into the growing mound beside it. Some researchers have proposed alternative uses, including brewing, hide-working, or bathing.

Burnt mounds of this kind are generally dated to the Bronze Age, roughly between 1800 and 800 BC, though some examples have been found to extend into the Iron Age. Mayo has a considerable number of recorded examples, which is partly a reflection of the county's extensive bogland, where waterlogged conditions preserve organic material and prevent agricultural disturbance from destroying the mounds entirely. The Cogaula example sits within this broader pattern of Bronze Age activity in the west of Ireland, where communities left behind relatively few monumental structures but considerable evidence of daily or seasonal life in the form of these modest, practical accumulations of stone and ash.