It is a rath, the most common type of ringfort found across Ireland, typically consisting of a raised circular bank enclosing a domestic space used during the early medieval period, roughly between the fifth and twelfth centuries. This one measures thirty-two metres in diameter and is defined by two concentric banks with a fosse, or ditch, running between them, a double-banked arrangement that would originally have suggested a settlement of some local importance.

The Clonbrock estate was the seat of the Dillon family, later the Barons Clonbrock, and the demesne that surrounds the site reflects centuries of managed landscape, the kind of environment in which earlier archaeological features can survive simply because the land was never intensively ploughed. The rath, however, has not escaped entirely unscathed. The outer bank shows numerous breaches that appear to be modern intrusions rather than ancient wear, the result of agricultural access or drainage work carried out long after the earthwork ceased to have any practical function. What remains gives a reasonable impression of the original circuit, but the detail is largely gone.