The one at Liscolman, settled into a gently sloping natural hollow on the northern edge of a stream in County Wicklow, is trivallate, defended by three concentric rings of earthen banks and ditches. That degree of elaboration is comparatively rare and suggests this was not an ordinary early medieval farmstead. The outermost bank, up to nine metres wide in places, survives fully only on the southern side; elsewhere its course is betrayed by what surveyors call differential growth, the way buried earthworks alter the vegetation above them in ways that become readable from ground level or from above.

The monument as it survives measures roughly 26.5 metres north to south and 23.5 metres east to west internally, with an external diameter of around 74.5 metres taking in all three circuits. Each bank is separated from the next by a fosse, the term for the ditch that typically accompanied such earthen enclosures and whose upcast material helped build the bank beside it. The entrance, positioned on the western side, is funnel-shaped, narrowing from about 2.4 metres at the outer bank to just one metre at the inner, with a causeway carrying the approach across the innermost fosse. This kind of controlled, narrowing passage would have made any approach to the interior deliberate and slow. A field boundary has since cut across the eastern portion of the site, and no internal features have been recorded, leaving open the question of what the enclosed space once held.