A ringfort, or rath, is a roughly circular enclosure, typically defined by an earthen bank and an outer ditch, that served as a farmstead or small settlement during the early medieval period in Ireland. At Sheefin, the earthen bank and its accompanying fosse, the external ditch that once reinforced the enclosure, have been worn so low that the site is no longer visible to anyone walking across it. The only way to confirm it is still there at all is through a faint crop mark picked up in a Digital Globe aerial photograph taken in November 2011, where differences in soil moisture and vegetation growth ghost the outline of the old circular form back into view from above.

The site was still legible, at least on paper, in 1837, when it appeared on the Ordnance Survey Fair Plan map as a circular earthwork marked simply as a fort. By 1970, when it was formally described, the structure measured approximately 30 metres in diameter and was enclosed by a very poorly preserved earthen bank and a slight external fosse. Even then, the bank was only traceable along its northern and eastern arc, and the fosse barely registered along the southern and north-western edges. A field fence had already begun curving along the perimeter, following the old outline as if the land itself remembered what had been there. A second ringfort lies roughly 70 metres to the east-south-east, and the ridge location, with its good views to the south-east and south-west, suggests this was once a more purposeful and inhabited stretch of ground than it appears today.