A broad earthen bank, two metres high and equally wide, traces a near-perfect circle in the pasture at Carrigeen, enclosing a space roughly forty-three metres across. Outside the bank runs a shallow fosse, the whole earthwork stretching to around seventy-five by eighty-five metres at its widest. The interior rises gently toward its centre, a subtle but deliberate shaping of the ground that gives the site a quietly purposeful geometry. This is a rath, the Irish term for a ringfort, the most common surviving monument type in the Irish countryside. Thousands were built across the island, mostly during the early medieval period, serving as enclosed farmsteads for a single family or household. Most people drive past several without ever noticing them.

When Kevin Danaher documented this site in 1955, he noted a causeway at the north-east, providing a raised crossing over the fosse, with the main entrance oriented to the east. That eastward facing is not unusual in ringforts; it appears frequently enough across the country to suggest it was a deliberate choice, though whether for practical, symbolic, or astronomical reasons remains a matter of discussion among archaeologists. The bank at Carrigeen is well preserved, its height and breadth still legible in the landscape despite sitting in working farmland. The slight rise on which it sits would have given its original occupants a modest but real advantage in terms of drainage and visibility across the surrounding ground.