But the bisecting trench and the depressions on either side of it are the giveaway: this is a fulacht fia, a type of prehistoric cooking site found in their hundreds across Ireland, typically consisting of a burnt mound of fire-cracked stone beside a water trough. Here at Dangan, that trough appears to survive as two distinct depressions in the ground, the deeper of the two reaching down 1.45 metres on the western side.

The mound itself is well-preserved and substantial, measuring roughly 23 metres along its longest axis and rising to between 1.2 and 1.6 metres at its highest point, which puts it at the larger end of the scale for such sites. The narrow trench running through it may have served as a channel to carry water from the nearby natural spring well, just 15 metres to the east, directly into the troughs. The general principle of a fulacht fia involves heating stones in a fire, dropping them into a water-filled trough to bring it rapidly to a boil, and using that heated water to cook meat or, as some researchers have proposed, for other communal purposes entirely. At Dangan, the landscape seems almost designed for it: the site sits in a natural hollow, sheltered on all sides except the west by higher rocky ground, with a reliable spring immediately adjacent. Tim Robinson noted this site on his 1997 map of the Burren, which suggests it was recognisable enough on the ground even then to merit inclusion among the region's features worth recording.

The spring well nearby has been given a modern enclosing wall at some point, marking it as a place still acknowledged even if its ancient connection to the mound beside it is easily overlooked. The karst terrain of the Burren, with its exposed limestone and thin acid soils, does not always preserve organic material well, but earthworks like this mound can endure for millennia when left undisturbed on the surface.