It is, in fact, a fulacht fia, one of the most common yet persistently mysterious monument types in the Irish landscape. These are the remains of Bronze Age cooking sites, where stones were heated in fire and dropped into a water-filled trough until the water boiled. The discarded, heat-cracked stones accumulated over repeated use into the characteristic crescent shape that survives today at thousands of locations across Ireland.

The mound at Gortavehy measures twelve metres in length, eight metres in width, and stands about a metre high, with its opening facing west towards the stream it once drew water from. The two terminals of the horseshoe had already been clipped by a pathway when the site was first recorded, and burnt material was visible in section along the stream bank, exposed by erosion or cutting. By the time someone returned to check on it in November 1993, the mound had been levelled. What had been a legible, reasonably intact feature was gone, the material spread or removed, leaving only the documentary record of its dimensions and form.