Subcircular in shape and measuring roughly 53 metres east to west and nearly 60 metres north to south, it rises to an external height of about 2.35 metres, its top almost level, the whole thing suggesting a deliberate, carefully constructed presence rather than a natural feature. A road now defines its eastern edge, and within the interior the traces of a hut site survive, a modest rectangular footprint roughly 9.5 metres by 5.3 metres.

This kind of earthwork is broadly classified as a raised enclosure or ringfort, one of the most common monument types in Ireland, though their individual histories vary considerably. What makes the Dunowen example quietly interesting is its local reputation. The antiquarian T. J. Westropp, writing between 1914 and 1916, recorded the local belief that this earthwork represented the original fort of Dunowen, describing it as a larger earthwork of the low mote type, a low motte being a raised earthen mound associated with early medieval or later defensive and residential use. By 1842 it was already significant enough to be marked with hachuring on the Ordnance Survey six-inch map, the standard cartographic shorthand for an earthwork feature. There is also a tradition of a souterrain beneath the site, an underground stone-lined passage or chamber of the kind that appears frequently in early medieval Irish settlements, typically interpreted as a place of storage or refuge.