What makes it quietly anomalous is not grandeur but persistence: agricultural land has been ploughed and reploughed around it for centuries, yet the enclosure survives, its earthen banks still legible in the landscape.

This is a rath, the Irish term for a ringfort, the most common monument type in the Irish countryside. Ringforts were typically the farmsteads of early medieval Ireland, roughly the fifth to twelfth centuries, enclosed by one or more circular banks and ditches to define a household's space and provide a degree of protection for people and livestock. At Ballyshane the enclosure measures 35.4 metres across on its north-south axis, making it a modest but respectable example of the type. An earthen bank rises to a maximum internal height of 1.4 metres on the south-east to north-east arc, accompanied by an external fosse, the ditch dug to provide material for the bank itself. A second, outer bank reaching 1.2 metres survives from the south around to the north-east, suggesting this was once a bivallate fort, one with two concentric enclosing banks, a form sometimes associated with higher-status occupation. On the northern side, however, that outer bank becomes insubstantial, and along parts of its circuit it has been absorbed into the modern field fence system, the boundaries of two different eras quietly overlapping.