This is a rath, the most common type of early medieval enclosure in Ireland, built as a raised bank of earth to define and protect a family's dwelling. Most were constructed roughly between the sixth and tenth centuries, and while they dot the Irish countryside in their thousands, this one carries a particular quality of persistence: the bank has been absorbed into the modern field fence system, meaning the farm boundaries of the early twenty-first century are still, at least in part, following the decisions of early medieval farmers.

The enclosure measures approximately thirty metres east to west and just under twenty-nine metres north to south, making it a relatively modest example of the type. The earthen bank stands around a metre high on the exterior along its south-western to northern arc, with a grass-covered scarp of up to 0.85 metres surviving elsewhere. There is a break in the bank to the north-north-west, which may indicate the original entrance. About 160 metres to the west, a second ringfort has been recorded, suggesting this part of Killinane was a settled and organised landscape in the early medieval period, with neighbouring enclosures positioned within sight or easy reach of one another.