It measures roughly twelve metres long, nine metres wide, and less than a metre high, with a circular depression at its centre and what appears to be an opening facing west. That description is almost exactly what archaeologists look for when they identify a fulacht fia, and this one at Carragraigue fits the profile closely.

Fulachtaí fia (the plural form) are among the most common prehistoric monuments in Ireland, found in their thousands across the country, almost always near water. The name translates loosely as "cooking place of the deer", though their exact function has been debated for decades. The prevailing interpretation is that they were used for boiling water: stones were heated in a fire, then dropped into a water-filled trough, raising the temperature quickly enough to cook meat or serve other purposes. Over time, the repeatedly cracked and discarded stones built up into the characteristic horseshoe or oval mound of dark, shattered material that survives today. Most date to the Bronze Age, broadly between 1500 and 500 BC, though some are older or younger. The marshy ground and proximity to the stream here at Carragraigue would have made it a practical location, providing both water and the soft, diggable earth needed to line a trough.