Most of Ireland's thousands of raths, the circular earthwork enclosures that dot the countryside and date broadly from the early medieval period, present at least some trace of a break in their banks where people and livestock once passed through. The one at Balleese in County Wicklow offers nothing of the sort, its perimeter apparently unbroken, which lends the place a quietly puzzling quality that goes beyond the usual archaeology.

The fort sits on a slight rise created by a natural rock outcrop amid gently rolling ground, a position typical of how these enclosures were sited: visible enough to assert presence, without requiring any dramatic hilltop. The circular interior measures twenty-eight metres across on its north-south axis, and the surrounding bank is substantial, roughly three and a half metres wide, with an internal height of somewhere between one and one and a half metres and an external face rising to between one and a half and two metres. The bank has drystone facing on both its inner and outer sides, and this stonework appears to have been tidied up relatively recently, which means what a visitor sees today is not entirely the raw texture of an early medieval construction. The interior itself is uneven, studded with rock outcrops and hollows, suggesting the ground was never levelled or heavily modified inside the enclosure.