This ringfort at Seafield sits with a direct line of sight onto Knocknarea, the great flat-topped hill on the Atlantic horizon whose cairn-capped summit is traditionally associated with the legendary queen Medb. The proximity is worth pausing over, not because the connection is provable, but because the early medieval farmers who built and lived within this enclosure would have looked out at that same profile every day.

A ringfort, sometimes called a rath, is the most common field monument in Ireland, typically a circular or oval enclosure defined by an earthen bank and ditch, used as a farmstead during the early medieval period, roughly between 500 and 1000 AD. The Seafield example is modest in scale, measuring approximately 21.80 metres in length and 16.80 metres in width, with an unusual outline: the western end is flattened, the north-western and south-western corners are angular rather than rounded, and the eastern end comes to a gentle point. This kind of irregular geometry, departing from the more expected round plan, gives the site a slightly distinctive character among its type. The enclosing bank is built of stone, between 2.30 and 2.60 metres wide and surviving to a height of between 0.60 and 0.75 metres, with rubble added to the northern side at some point. The interior itself is not level; the ground slopes downward from west to east, which would have made the choice of this particular hillock a deliberate one, offering elevation and outlook at the cost of a slanted living surface.