The earthwork is subtle enough that a casual walker might cross it without registering what it is, yet its geometry is deliberate and its origins are old.

This is a rath, the most common type of early medieval settlement monument in Ireland, typically consisting of a circular area enclosed by one or more earthen banks and ditches. At Skreen Beg, the enclosure measures roughly 24 metres north to south and 21 metres east to west. The defining bank, now heavily reduced by time and agriculture, survives to an internal height of just 0.4 metres and a width of 3.6 metres. Along the south-west to north-west arc, the bank has disappeared entirely; what remains there is only a scarp, a low, abrupt edge in the earth, doing the same work of marking the perimeter. No fosse, the external ditch that typically accompanied such banks, is visible at ground level, suggesting it has been ploughed or silted into obscurity over the centuries. The most legible feature is the original entrance, a 4-metre gap in the bank on the eastern side, accompanied by an external ramp that would once have helped livestock and people pass in and out. Less explicable are the small quarry holes dug into the bank at the north and west, intrusions whose purpose is unclear but which speak to later, pragmatic use of the structure long after its founding function had been forgotten. At the centre of the enclosed area, a house site is recorded, the ghost of a dwelling that once stood within the protection of the bank.