Measuring roughly 64 metres in diameter, it is one of the larger examples of its type, yet its outline is now so absorbed into the working landscape that three separate field walls cut straight through it, dividing what was once a unified enclosure into disconnected fragments.

Ringforts, known in Irish as raths or liosanna, were the dominant settlement form in early medieval Ireland, typically consisting of a circular area enclosed by one or more earthen banks and ditches, used as farmsteads by local families of some standing. The example at Dún Sheáin retains only a slight scarp, the gentle earthen step that once formed its boundary, where a more pronounced bank may originally have stood. Because it escaped cartographic notice entirely, its survival owes nothing to official recognition and everything to the accident of the field walls that, in cutting through it, also inadvertently preserved its general shape within the agricultural fabric of the hillside. The site was documented by J. Cuppage in the 1986 Corca Dhuibhne archaeological survey of the Dingle Peninsula, a substantial regional survey that brought a number of previously unrecorded sites like this one into the archaeological record for the first time.