It is easy to mistake for a natural rise in the ground, but the burnt stone and charcoal compressed into its bulk tell a different story, one that stretches back to the Bronze Age.

This is a fulacht fia, a type of site found in considerable numbers across Ireland and particularly abundant in Munster. The term, sometimes translated loosely as "wild deer cooking place", refers to the remains of an ancient outdoor cooking method. The typical arrangement involved a trough dug into the ground near a water source, which was filled with water and heated by dropping fire-cracked stones into it until the water boiled. The stones, once spent, were discarded in a heap alongside the trough. Over centuries and millennia, these discarded heaps accumulated into the horseshoe-shaped or oval mounds that survive today. The Grenagh example measures roughly 16.7 metres north to south and 22.7 metres east to west, making it a reasonably substantial example. The springs immediately to its north and south would have supplied exactly the kind of reliable water source these sites depended upon, and their presence here almost certainly explains why this particular spot was chosen.