This one, atop an east-west ridge with views north towards the River Blackwater, has been quietly absorbed into the working landscape of Rathduane House, its ancient geometry slowly overtaken by agricultural necessity.

Ringforts, sometimes called raths, were typically constructed between roughly the fifth and twelfth centuries as enclosed farmsteads, their earthen banks and ditches, known as fosses, providing both a degree of security and a clear statement of status. The Rathduane example was originally circular, around forty metres in diameter, enclosed by a bank with a second bank running from the south-south-east to the north-west. By the time it appeared on the 1938 Ordnance Survey six-inch map, it was already partly reduced, and today only the double earthen bank running from the south-south-west to the north-west survives with any real presence, the inner bank standing about one metre high and the outer slightly more at around 1.15 metres. Both banks are now lined with mature deciduous trees. The interior has been encroached upon by the farmyard of Rathduane House, with a large shed constructed in the south-west quadrant. Perhaps the most intriguing detail is a local tradition that a souterrain lies within the interior. A souterrain is an underground stone-built passage or chamber, typically associated with ringforts and thought to have served for storage or as a place of refuge, and its possible presence here suggests the site was once a more substantial settlement than its present state implies.