It measures roughly five metres across and stands only about forty centimetres high, yet it represents one of the more persistent mysteries in Irish archaeology.

This is a fulacht fia, a type of site found in the hundreds across Ireland, typically dating to the Bronze Age. The name, loosely translated from Old Irish, refers to a cooking place associated with hunters or wandering bands, though the precise interpretation has long been debated. In the classic form, a fulacht fia consists of a horseshoe-shaped mound of fire-cracked stone surrounding a sunken trough. The usual theory holds that stones were heated in a fire, then dropped into a water-filled trough to bring it to a boil for cooking meat. The stones, shattered by repeated heating and quenching, were discarded into the surrounding mound over time, gradually building up the characteristic low ridge visible at thousands of sites today. What makes Rathlogan slightly unusual is that no visible trough depression survives here; if there was ever a wooden or stone-lined pit, it has either collapsed and filled, or was never cut deeply enough to leave a lasting impression at the surface. The mound itself, circular rather than the more typical horseshoe shape, and positioned immediately beside a stream, fits the broader pattern of such sites being sited near reliable water sources.