The enclosure measures roughly 46 metres north to south and 42 metres east to west, enclosed by an earthen bank that still stands 1.8 metres high in places, with a shallow external fosse, or ditch, running around the outside. That the fosse survives at only 0.2 metres deep suggests considerable silting and erosion over the centuries, yet the overall form remains coherent enough to read.

This kind of monument is known as a rath, the most common archaeological site type in Ireland, with tens of thousands recorded across the country. Raths were enclosed farmsteads, typically built during the early medieval period, roughly between the fifth and twelfth centuries, and used to protect a family's home, livestock, and status within the local social order. The earthen bank and ditch combination was less about serious military defence and more about defining a boundary, keeping animals in and wolves out, and signalling that the people inside occupied a recognised position in the landscape. The two gaps in the bank at An Tóchar, a wider one to the south-east at 2.6 metres and a smaller one to the north-west, are likely original entrance points, though it is not always easy to distinguish deliberate gaps from later breaks caused by field clearance or casual passage over the centuries.