It measures roughly fifteen and a half metres east to west and just over twelve metres north to south, rising to about sixty centimetres at its highest point. Beneath the grass, the mound is composed of burnt material, the characteristic signature of a fulacht fia, one of the most common yet least understood monument types in the Irish landscape.

Fulachtaí fia, found in their thousands across Ireland, are the remains of ancient cooking or industrial sites, typically dating from the Bronze Age. The usual interpretation is that water was heated in a trough by dropping fire-cracked stones into it, and those stones, once spent, were piled to the side. Over centuries, these discarded heaps of shattered, scorched stone accumulated into the horseshoe-shaped or oval mounds that survive today. The boggy, waterlogged ground at Ceann Droma would have made the site well suited to such activity, with a ready water source close at hand. Local knowledge adds a further detail: a second fulacht fia once stood just to the west of this one, but has since been levelled and is no longer visible above ground. The pairing of such sites is not unusual, though the loss of one reduces what might otherwise have been a rare opportunity to study two monuments in close proximity.