It stands only thirty centimetres above the surrounding field, measures somewhere between six and seven metres across, and is covered in grass and moss. What makes it worth pausing at is what lies beneath: a layer of black soil concealing a dense concentration of heat-shattered stone packed into charcoal-rich earth, the remains of a burnt mound.

Burnt mounds are among the most common prehistoric monuments in Ireland, yet they remain poorly understood. They are thought to date primarily from the Bronze Age, and the leading theory holds that they were cooking sites, where stones were heated in a fire, dropped into a water-filled trough to bring it to the boil, and then discarded in a pile once they cracked and became useless. Over time, repeated use built up a mound of fire-fractured stone and dark, charcoal-stained soil. The example at Carrowkilleen fits this pattern closely. The River Deel runs just twenty metres to the south, which would have provided a ready water source, and the ground rises gently to the north, offering some shelter. The mound's edges are indistinct, as is common with sites that accumulated gradually rather than being deliberately constructed. Running across it, and across the surrounding area, are traces of cultivation ridges on a north-south axis, suggesting the land was later worked for agriculture, probably in the post-medieval period, without whoever was farming it necessarily knowing or caring what lay underfoot.