The circular earthwork measures thirty-one metres across internally, defined by a bank only half a metre high and three metres wide, with a shallow external fosse, or ditch, that dips just thirty centimetres below the surrounding ground. There is no visible entrance, no trace of internal features, and a modern field boundary running roughly north-northeast to south-southwest cuts straight across the middle of it, dividing the monument as casually as if it were any other patch of ground.

This is a ringfort, the most common early medieval monument type in Ireland, typically dating from roughly the fifth to the twelfth century. Ringforts served as enclosed farmsteads, the earthen bank and ditch providing a degree of security for a family and their livestock rather than any serious military defence. The Commons Upper example is a slight one, which may indicate modest social standing, partial erosion over centuries, or simply the quality of the local soil. What makes the site particularly interesting from a documentary perspective is the evidence of how aerial photography has quietly tracked its fate. Aerials from 2005 show the field immediately to the west under the plough, pressure that would have threatened the monument's survival, while images from 2009 onward show the site leaving a visible trace in the landscape once again. The record was compiled by Geraldine Stout and later updated by Christine Baker, with the entry uploaded in October 2014.

The site sits in rough pasture, which means the ground is uneven and can be wet underfoot depending on the season; stout footwear is advisable. Because the bank is so slight, the earthwork reads better from a slight elevation or in low winter light, when raking sunshine throws even shallow undulations into relief. The bisecting field boundary is the most immediately obvious feature on the ground, and following its line north-northeast will help orient you to the two surviving arcs of the bank on either side. There is no formal access or signage, so the usual courtesies around farmland apply.