It is a fulacht fia, a type of ancient cooking site found in considerable numbers across Ireland, typically dating from the Bronze Age. The basic idea was straightforward: stones were heated in a fire and then dropped into a water-filled trough, bringing it to a boil rapidly and repeatedly. The burnt and shattered stones were discarded to the sides over time, which is precisely what created the characteristic crescent-shaped mound that survives today.

The Finuge example measures eight metres along its north-south axis, and the incurve of the horseshoe faces west. The opening into the central working area is about 3.3 metres wide, leading into a rectangular depression measuring 4.4 metres by 5 metres, which would once have held the trough. That the site sits in marshy ground is no accident. Fulachtaí fia are almost always found near water or in low-lying, wet terrain, both because the trough needed a ready water supply and because such ground was less useful for agriculture and therefore less likely to be disturbed. The combination of waterlogged conditions and relative isolation has helped preserve the mound's shape across several thousand years.