Look more closely at the aerial record, however, and something older begins to resolve itself: a nearly circular enclosure roughly fifteen to sixteen metres across, its outline still faintly legible from above even after the earthwork that once defined it has been ploughed almost entirely flat.

The site at Ballynamona appears on the 1897 edition of the Ordnance Survey's 25-inch map as a raised, roughly circular area defined by a scarp and a fosse, which is simply a ditch dug around an earthwork to reinforce it. A field boundary already intersected it along the western and northern arc by that date, following the curve of the monument as though acknowledging it. When archaeologist Celie O'Rahilly visited for Limerick Corporation in 1994, she recorded a slightly raised area enclosed by a well-defined bank, with traces of an outer fosse surviving to the north-east and west, and an entrance gap to the south. The classification of the site has not been entirely settled. T. B. Barry, writing in 1981, listed it as a possible moated site, a category that usually refers to a medieval enclosed farmstead surrounded by a water-filled ditch, commonly associated with Anglo-Norman settlement. The dimensions here are on the small side for a classic moated site, which leaves the question of origin quietly open. A preservation order was placed on the monument in October 1994, though the earthwork had already been largely levelled by that point.

The enclosure sits in reclaimed pasture about 125 metres north of a watercourse, which is a typical locational logic for this kind of monument: access to water, slightly elevated ground. On the ground today, the most visible surviving element is the curving field boundary along the northern edge, which traces the old perimeter. Aerial images, including those available through Google Earth, give the clearest sense of the original form; the cropmark or soil differential can show up well depending on the season and the state of the vegetation. There is nothing dramatic to find at the surface, but that is rather the point: the place rewards the kind of attention that reads landscape as a palimpsest, where what has been erased still leaves a faint impression.