Roughly circular, measuring about 5.8 metres north to south and 5.6 metres east to west, and rising to only around 0.45 metres in height, it is easy to overlook entirely. What it actually represents is the accumulated debris of repeated prehistoric cooking, a fulacht fia, the term used for a type of Bronze Age cooking site found in enormous numbers across Ireland and particularly concentrated in Munster.

A fulacht fia typically consists of a trough dug into the ground, usually lined with wood or stone, which would have been filled with water. Stones were heated in a nearby fire and dropped into the trough to bring the water to a boil, and the cracked, fire-shattered fragments of those stones, discarded after use, built up over time into the horseshoe or crescent-shaped mound that survives today. The burnt and blackened material underfoot in places like Kilnahulla More is largely this shattered stone, mixed with charcoal and organic matter. What makes this particular site especially notable in a quiet, cumulative way is that it does not stand alone. It is one of a cluster of five such monuments in the immediate area, suggesting the location held some sustained significance for the communities who returned to it, possibly over generations.