This particular one, the middle of the group in terms of proximity, is barely perceptible as a raised feature at all, occupying a slightly drier hummock in the soggy ground around it.

A ring-barrow is a burial mound of the Bronze Age tradition, typically consisting of a central raised area ringed by a ditch, or fosse, and an outer earthen bank. The example at Duncummin is small even by the standards of the type: the central platform measures just three metres in diameter, enclosed by an earthen scarp only twenty centimetres high, with a shallow fosse and a low outer bank whose total width across all its elements reaches less than two metres. What remains is compact, geometrically clear, and surprisingly intact. The interior is level and free of overgrowth, which makes the concentric structure easier to read than many comparable monuments that have been obscured by scrub or disturbed by later farming. Its two companions lie close by, one sixteen metres to the south-west, another seventy metres to the north-west, suggesting this corner of Tipperary was, at some point in prehistory, a deliberate place of burial rather than an incidental one.