It measures just over thirteen metres north to south and a little over ten metres east to west, rising to about one and a half metres at its highest point. The opening on the southern side is three and a half metres wide. None of this would look remarkable to a passing eye, but the mound is composed almost entirely of burnt material, the accumulated debris of repeated prehistoric cooking episodes stretching back perhaps three or four thousand years.

This is a fulacht fia, a type of site found in enormous numbers across Ireland, particularly in low-lying or waterlogged ground close to a water source. The basic principle involves heating stones in a fire until they are intensely hot, then dropping them into a water-filled trough to bring it rapidly to the boil. The stones crack and shatter with the thermal shock and cannot be reused, so they are discarded to the side of the trough after each use. Over time, and over many generations of use, these rejected burnt and broken stones accumulate into the characteristic horseshoe or kidney-shaped mounds that survive today. The site at Knockeenadallane fits this pattern closely: marshy ground, proximity to a stream, and that distinctive low crescent of fire-cracked material. What makes the location quietly notable is that a second fulacht fia lies only about a hundred metres to the south-east, suggesting this particular stretch of north Cork countryside was a place people returned to repeatedly, for cooking, for processing, or perhaps for purposes that remain debated among archaeologists.