The interior is now entirely sealed off by encroaching bushes, which means the rath at Clashelane is, in a practical sense, a monument you can only observe from the outside, reading its shape rather than entering it. That shape, roughly twenty-five metres in diameter, is the footprint of a ringfort, a type of enclosed farmstead that was the most common form of rural settlement in early medieval Ireland, built and occupied broadly between the fifth and twelfth centuries.

The surviving earthwork follows a pattern recognisable across thousands of similar sites throughout the country. An earthen bank encircles the interior, standing about half a metre high on the inside and slightly more on the exterior, at around eighty centimetres. Beyond the bank, a fosse, essentially a ditch dug to provide the material for the bank itself, runs from the eastern side round to the south, with a shallower depression traceable to the north. The bank's surface is scattered with loose and partially embedded stone, which may reflect later disturbance or simply the gradual exposure of material over centuries. A formal entrance gap, about three and a half metres wide, opens to the northeast. This north-easterly orientation is not unusual for ringforts; it may reflect practical considerations around prevailing wind or simply the lie of the land on any given site.