That kind of casual truncation is not rare in Ireland, but it gives this particular site an oddly exposed quality, the ancient and the everyday pressing hard against each other.

A ringfort, or rath, is a roughly circular enclosure defined by one or more earthen banks and ditches, typically dating from the early medieval period and associated with farming settlements. The Glascarn example was already recorded on the Ordnance Survey six-inch map of 1837, where it appears as a circular earthwork sitting directly against the public road to its east. By the time the revised twenty-five-inch map was produced in 1913, a field boundary had further compromised the northern side. When the monument was formally described in 1980, surveyors found an oval enclosure measuring roughly 34 metres north to south and 29.5 metres east to west, defined by a bank of earth and stone with an external fosse, the ditch that would once have reinforced the sense of enclosure and demarcation. No original entrance gap was identifiable. The bank retained some internal stone facing on its southern arc, though elsewhere it had been worn down to little more than a low scarp. The fosse itself survived in reasonable depth around the southern and western sections but grew shallower toward the north, where partial infilling had reduced it further. A modern field fence now bisects the interior from roughly northwest to southeast. Another ringfort lies approximately 90 metres to the southeast, suggesting this part of Westmeath once supported a cluster of such enclosed settlements on its gently rolling pasture. Aerial photography shows the monument today as a tree-planted oval, the canopy rendering visible from above what the surrounding fields might otherwise obscure at ground level.