It is horseshoe-shaped, nearly two metres high, and its open end faces a small, fast-moving stream just a metre away. That deliberate orientation is the first clue to what this structure actually is, and what it was built to do thousands of years ago.

This is a fulacht fia, a type of prehistoric cooking site found in large numbers across Ireland, particularly in low-lying or waterlogged ground near running water. The typical method involved heating stones in a fire, then dropping them into a water-filled trough to bring it rapidly to the boil; the crescent or horseshoe shape of the surrounding mound is the accumulated debris of those shattered, heat-cracked stones, built up over repeated use. The trough at Gortacareen measures three metres by three and a half metres, and the whole site extends twelve metres north to south and eight metres east to west, making it a notably large example of the type. The proximity to the stream, one metre to the west, would have been essential for keeping the trough supplied with water. The site is documented in F. Coyne's 2006 upland archaeological study of Mount Brandon and the Paps, published by Kerry County Council in association with Aegis Archaeology, which recorded it sitting in partially reclaimed marsh, a landscape that has probably not changed dramatically since the site was in active use.

The boggy ground around the mound is something a visitor would notice immediately. The field may look ordinary enough from a distance, but the soft underfoot conditions are a reminder that the people who built this structure chose their location carefully, seeking out exactly this kind of wet, stream-fed terrain. The mound itself, covered in grass, is substantial enough to read clearly in the landscape once you know what to look for.