Measuring roughly 18 metres northwest to southeast and 14 metres southwest to northeast, with its opening facing west, it is a quiet anomaly among the turned earth, the kind of feature most people would walk past without a second thought.

What it represents, however, is a technology practised across Ireland for well over a thousand years during the Bronze Age. A fulacht fia, sometimes called a burnt mound, is the archaeological remains of an ancient cooking or processing site. The typical method involved heating stones in a fire, then dropping them into a water-filled trough to bring the water to the boil. The stones crack and shatter with repeated use, and over time the discarded fragments accumulate into the characteristic horseshoe-shaped mound that survives today. The association with water is telling at Glenarousk too: a well lies close by to the northeast, which would have provided a ready source. Interestingly, the site does not stand alone. A second fulacht fia sits roughly 36 metres to the southeast, suggesting this particular area of Cork was a place of some repeated or communal activity in prehistory, rather than a single isolated episode.