It is roughly eleven metres across and rises just over a metre at its highest point, built largely from burnt stone. Along its northern edge, facing the water, a rectangular depression measuring six metres by one and a half metres marks what was once a trough. Locals know the spot as Ardnawillan.

This is a fulacht fiadh, a type of prehistoric cooking site found in great numbers across Ireland, typically Bronze Age in origin. The basic principle was straightforward: a trough, often timber-lined and filled with water, would be heated by dropping fire-cracked stones into it until the water boiled, at which point meat could be cooked. The spent stones, cracked and blackened from repeated heating, were piled nearby, gradually forming the horseshoe-shaped or oval mounds that survive today. At Ardnawillan, that accumulation of discarded stone forms the mound as it now stands. Thirty metres to the west, a low spread of burnt stone and blackened soil may point to a second such site, suggesting this particular stretch of marshy ground, close to fresh water and perhaps seasonally used, drew repeated activity over time. The archaeological survey of the Iveragh Peninsula, compiled by A. O'Sullivan and J. Sheehan and published by Cork University Press in 1996, records both features.