To most eyes it would read as nothing more than a slight unevenness in the land. To an archaeologist, it is the last legible trace of a ringfort, the circular earthwork enclosure that once formed the defended farmstead of an early medieval Irish family. Thousands of these structures survive across Ireland in varying states of preservation, but this one in Smithfield has been almost entirely levelled, leaving only the faintest impression where its single bank once stood.

The site was recorded clearly enough on the Ordnance Survey six-inch map of 1842, where it appeared as a hachured circular enclosure roughly twenty-eight metres in diameter, the standard cartographic shorthand for an earthwork of this kind. By the time the antiquarian Bowman noted it in 1934, it was already one of two such levelled ringforts on land belonging to a W. Mullane, both of them reduced to something close to nothing. The pair would have been single-ramparted examples, meaning each originally consisted of one earthen bank and, most likely, an accompanying outer ditch enclosing a domestic interior. The gentle slope of the surviving depression down toward the north-east is about all that now hints at the original form of the enclosure.