Eighteen metres across and defined by a stone bank roughly a metre and a half wide and half a metre high, it retains an inner and outer revetment of small boulders, meaning the bank was carefully faced on both sides rather than simply piled up. That kind of construction suggests deliberate effort, yet the site's purpose remains uncertain. It may have been a hut site, a modest domestic enclosure of the kind found throughout prehistoric and early medieval Ireland, though that tentative identification has never been confirmed.

The proximity to Rathgall is the most compelling detail here. Rathgall is one of the major later Bronze Age hillforts in Leinster, a large multivallate enclosure with a long history of occupation, and the small enclosure at Knockeen sits almost in its shadow. Whether the two were contemporary or connected is unknown, but the relationship in the landscape is difficult to ignore. Grosvenor Hodge Orpen, the historian and scholar of medieval Ireland who noted this site in 1930, recorded it alongside other features in the area, though his reference does little more than establish that the enclosure was already known and already partly obscured by that point.

Today the site is partly masked by dumped material, which limits what the surface can tell a visitor or even a surveyor. The stone bank is still present in some form, but reading it clearly would require more than a casual walk across the slope.