What makes the rath at Aughnagomaun particularly telling is a patch of damage along its northern edge: the outer face of the bank has been quarried into at some point, and the exposed section reveals how the structure was originally built, with loose rubble laid on top of earthen foundations. It is an accidental cross-section through early medieval engineering, left open for anyone who looks closely enough.

Ringforts, known variously as raths or cashels depending on whether their enclosing bank is earthen or stone, were the most common form of rural settlement in early medieval Ireland, typically serving as enclosed farmsteads for a single family and their livestock. The Aughnagomaun example is a raised circular platform measuring roughly 35 metres north to south and 33 metres east to west, ringed by a bank that stands 1.7 metres high on its exterior face. On the south and west sides the bank has been reduced to a simple scarp, the more steeply defined profile of the north and east giving a sense of how prominent the enclosure would once have appeared across the landscape. There are faint traces of a fosse, the external ditch that typically accompanied such a bank, though it has silted up to the point of being barely discernible. At the north-east, a gap just over a metre wide may represent the original causewayed entrance, the raised approach across a ditch that was a common feature of rath design. Roughly 370 metres to the south-east lies a moated site, a different class of monument associated with Anglo-Norman settlement, suggesting this particular stretch of Tipperary farmland was attractive to successive communities across several centuries.