It extends roughly a hundred metres in a fairly straight line to the north-east before curving eastward for about twenty-five metres, and a second curving stretch of approximately forty metres sits around ten metres to the north of it. The banks have some visible remains at ground level, though they are unspectacular to the casual eye. What makes them worth pausing over is what they appear to be attached to.

The boundary abuts the north-eastern sector of a probable enclosure, the kind of roughly circular or oval earthwork that recurs throughout the Irish landscape and typically dates to the early medieval period, though enclosures of this form were in use across a much wider span of prehistory. The enclosure itself is not visible on the ground at all; it only becomes apparent as a cropmark on satellite imagery from around 2010. Cropmarks form when buried features such as ditches or banks affect how vegetation grows above them, producing tell-tale differences in colour or height that become legible from the air, particularly during dry summers when soil moisture variation is most pronounced. The field boundary in Nooaff is, in that sense, a fragment of something larger, a surviving above-ground remnant attached to a feature that has otherwise been absorbed entirely into the soil.