What makes the site at Scullaboge quietly arresting is the gap between what the cartographers of 1839 thought they were recording and what is actually there. The first edition Ordnance Survey six-inch map, produced that year as part of Ireland's remarkable early national mapping effort, marks the feature as a circular embanked enclosure roughly fifty metres across. On the ground, however, the shape is more accurately described as a D, measuring about 43.5 metres east to west and 31 metres north to south, and any original circularity has been interrupted at the northern edge by a later east-west field bank that simply cuts across it.

An embanked enclosure of this kind, a defined area enclosed by an earthen bank rather than a wall or ditch, is a form that appears across Ireland in various periods and contexts, from early medieval farmsteads to ceremonial or funerary sites of much greater antiquity. At Scullaboge, the surviving earthwork is defined on its eastern and south-eastern to north-western arc by a scarp, essentially a sloped face of raised ground, standing between half a metre and 1.5 metres high. The bank itself, preserved most clearly on the north-eastern to eastern perimeter, is about seven metres wide and rises to an external height of 1.8 metres. Notably, there is no visible fosse, the encircling ditch that typically accompanies such a bank, and no identifiable entrance survives. Whether the fosse was never dug, has silted beyond recognition, or was removed by later land use, the record does not say.