What appears to be an ordinary paddock boundary turns out to be the softened remains of an early medieval enclosure, its sub-circular outline still legible in the landscape despite centuries of agricultural pressure. Ringforts, known in Irish as raths when built primarily from earth, were the standard farmstead type of early Christian Ireland, typically dating from around the fifth to the twelfth century. A family would have lived within the enclosed interior, with the surrounding bank and its accompanying fosse, or external ditch, providing a degree of security and a clear marker of territorial ownership.

The Rathnaseer example measures roughly 42.5 metres north to south and 41 metres east to west, making it a fairly typical specimen in terms of scale. The enclosing earthen bank survives best along the northwest to southeast arc, where it still stands to an external height of around 0.55 metres, dropping away more noticeably towards the south-southwest and west. A shallow external fosse, roughly 1.4 metres wide and just 0.1 metres deep, runs along the south-southwest to west and north-northwest to north-northeast portions of the circuit. The eastern and southern sides of the bank have been straightened and pressed into service as one edge of a modern paddock, though the fencing that once completed the other sides of that enclosure has since been removed. Mature trees now grow along the western portion of the bank, and there has been some dumping of earth, stone, and organic material against the outer face on the west to north-northwest side, which has not helped preservation. The record was compiled by Denis Power and uploaded in August 2011.

The interior is level and under pasture, so the site is most easily read from the slight elevation of the bank itself rather than from within. The northwest to southeast section gives the clearest sense of the original form, where the bank retains a reasonable profile and the distinction between inner and outer face is still apparent. A field boundary meets the outer edge of the fosse at the north-northwest, which can make the circuit a little harder to trace at that point. Because the earthwork is low and set into working farmland, it is easy to walk past without registering what you are looking at; knowing in advance that the slight rise underfoot is the remains of an enclosure used by a family perhaps a thousand years ago is what makes the difference.