It measures roughly eighteen metres north to south and seventeen metres east to west, and to an untrained eye it might pass for nothing more than a slight unevenness in the ground. Beneath the turf, however, lies a spread of burnt stone and charred material, the signature remains of a fulacht fia, a type of prehistoric cooking or processing site found in great numbers across Ireland.

Fulachtaí fia, the plural form, are among the most common archaeological monuments in the Irish countryside. The typical interpretation is that they functioned as outdoor cooking sites, where stones were heated in a fire and then dropped into a water-filled trough to bring it to the boil. The burnt and cracked stones, discarded after use, accumulated over time into the characteristic horseshoe-shaped mounds that survive today. The site at Garranmacgarrett lies about 180 metres east of a stream, consistent with the pattern of water proximity seen at fulachtaí fia elsewhere. It was recorded by Bowman in 1934, making it one of the earlier documented examples in the county. Notably, a second such monument lies approximately 150 metres to the south-west, suggesting that this particular stretch of north Cork saw repeated or sustained use over time, though whether the two sites were contemporary with one another is not something the surviving evidence can settle.