The site at Kilmacnevan was recorded and then erased almost simultaneously, levelled between 1972 and 1973, within a year or two of being properly described. What survives is only the description itself, a kind of ghost outline of something that was already fading when surveyors first noted it down.

A ringfort, sometimes called a rath, is a roughly circular enclosure defined by an earthen bank and, often, a shallow external ditch known as a fosse. They are among the most common field monuments in Ireland, typically associated with early medieval farming settlements, places where a family kept livestock and lived within a defined boundary. The example at Kilmacnevan was modest in scale, roughly 23 metres north to south and 20 metres east to west, sub-circular in shape, with an entrance gap of about 3.8 metres on the south-west side. Even in 1972 the bank was poorly preserved, already levelled along its southern and northern stretches. What made the interior particularly legible was the arrangement within it: a rectangular house site occupied much of the central space, with four low banks radiating outward from it towards the perimeter at the south-west, north-west, east-north-east and north-east. This kind of internal structure, a domestic building set within its enclosure and connected to the boundary by low dividing banks, gives a clear sense of how such a space was organised and used. The site sat on a natural rise with open views to the south-east, south-west and north-west, a position typical of these monuments, which were often placed to command the surrounding landscape without quite dominating it. A second ringfort survives 75 metres to the east. By the time aerial photography captured the area again in November 2011, nothing of the Kilmacnevan site remained visible on the ground.