What makes this particular rath, the Irish term for a roughly circular enclosed settlement typically dating from the early medieval period, more than ordinarily interesting is that the very boundary of two townlands runs through it. The stone and earth field fence dividing Monroe from Johnnstown curves around the monument along its western arc, in the process burying and obscuring the outer bank on that side. The landscape, in other words, has absorbed the archaeology and simply carried on.

The enclosure is sub-circular in plan, measuring approximately 30 metres north to south and 32 metres east to west, and is defined by two substantial earthen banks with a wide, deep fosse between them. A fosse is simply a defensive ditch, dug to reinforce the barrier created by the banks thrown up beside it. On the south-eastern side, both banks and the fosse have been quarried away, and a possible original entrance at that point is only partially legible now because of that damage. What does survive on the south-eastern arc is a causeway across the fosse, 7.5 metres wide and just under a metre high, which gives some sense of how the site would once have been approached. Inside the enclosure, two fragmentary banks run across the interior at different angles and appear to be later additions rather than part of the original design. In the south-western quadrant, a series of humps and hollows may represent the remains of a square-shaped hut site, hinting at domestic occupation within the rath at some point in its history. A separate earthwork lies roughly 70 metres to the south, suggesting this corner of Monroe held more than one focal point in the past.

The site sits in open grassland with clear views to the south and west, and the hillslope rising behind it to the east gives it a sheltered, slightly tucked-away quality. Visitors looking carefully at the ground in the south-western interior may be able to make out the subtle surface irregularities that suggest the possible hut site, though the most legible feature from ground level is likely the causeway, which retains genuine height and width despite everything the landscape has done to the monument around it.