Locally it goes by 'Daire's Hill', but the Irish place-name tradition is more specific: the Ordnance Survey Letters record that the parish name 'Dún Doighre' derives from a dún, a defended enclosure or fort, that stood on this very hill, known in Irish as Cnoc a dúin, the hill of the fort.

What survives today is a circular rath, a type of earthen ringfort that was a common form of settlement and enclosure across early medieval Ireland, roughly forty metres in diameter. It is not in good condition. The defining feature is a scarp, an artificially cut or built-up earthen edge, reaching about 2.3 metres at its highest point, but this gradually loses itself into the natural hillslope as it curves from the north-west to the north-east. The western sector has been further damaged by quarrying at some point, leaving that portion of the circuit indistinct. A church site lies approximately 250 metres to the south-west, a pairing of ecclesiastical and secular enclosure that is not unusual in the Irish landscape and hints at how this particular patch of east Galway was once more densely organised than its present emptiness suggests. The place-name evidence preserved in O'Flanagan's compilation of the OS Letters ties the identity of the whole parish back to this single, worn earthwork, which is a remarkable kind of durability for something so close to disappearing into the grass.