It stands just 1.3 metres tall, with a top diameter of 2.5 metres and a base spreading to 12 metres across. There is no enclosing bank and no fosse, the defensive ditch that typically rings this class of monument, which makes it an unusually bare example of its type.

A ring barrow is a prehistoric funerary mound, usually dating from the Bronze Age, raised over a burial and sometimes surrounded by a circular earthwork. This one at Clarkville carries none of that outer architecture, presenting instead as a low, rounded lump of earth with little to signal its age or purpose to the uninitiated eye. It sits on elevated ground with wide views across the landscape, a placement that was deliberate in prehistoric funerary practice, where prominent or commanding positions were often chosen for the burial of the dead. A second ring barrow lies nearby to the south, suggesting this corner of Offaly once held some significance as a place of burial or ceremony. The southern side of the mound shows signs of disturbance, most likely the result of grazing livestock over many years rather than any antiquarian interference.