It is recorded as a fulacht fia, one of the most common prehistoric monument types in Ireland, yet one that still prompts genuine debate among archaeologists. The term, sometimes rendered as fulacht fiadh, refers to a burnt mound, typically a horseshoe-shaped heap of fire-cracked stone and charcoal-blackened earth left behind by repeated episodes of water-heating. The leading theory holds that these sites were used for cooking, though proposals involving textile processing, bathing, and brewing have all attracted serious attention over the years.

What little is known about the Kilnahulla More example comes from cartographic evidence rather than any excavation. The mound appears on the Ordnance Survey six-inch map of 1937, suggesting it was already a recognised feature of the landscape by then, even if its nature was not necessarily understood by those who mapped it. When the site was assessed for the Archaeological Inventory of County Cork, the mound was visible on the surface but the presence of a mature crop in the surrounding tillage field made any closer inspection impossible. That is roughly the sum of the documented record: a shape on an old map, a low rise in a cultivated field, and an unresolved question about what lies beneath.