A fulacht fia is a type of ancient cooking site, found in enormous numbers across Ireland, typically consisting of a horseshoe or kidney-shaped mound of fire-cracked stones beside a water source or, as here, in naturally wet ground. The mound forms over centuries as heated stones, used to boil water in a trough, are discarded after use and gradually accumulate into a distinctive low rise.

The example at Knockadaumore is notably well preserved. The grassed-over mound measures roughly 19 metres along its north-northeast to south-southwest axis and around 10 metres across, rising to about 0.6 metres in height. At its centre sits a depression, approximately 4.9 metres long and 4.25 metres wide, opening to the west-southwest. This central hollow is where the trough would once have been located, the wooden or stone-lined pit into which water was poured and then brought to a boil by dropping in stones heated in an adjacent fire. The marshy, flat character of the surrounding landscape is entirely consistent with how these sites were used; access to water was essential, and low-lying boggy ground provided it reliably. Fulachtaí fia, as they are known collectively in Irish, date broadly to the Bronze Age, though some examples have produced dates ranging into the Iron Age and beyond.