Ringforts, known in Irish as raths, were enclosed farmsteads typically built during the Early Medieval period, roughly between the fifth and twelfth centuries. Most of the Irish landscape holds traces of them, but many have been levelled by ploughing or erased by development over the centuries. This one at Knockmorris has survived in good condition, its circular bank, outer ditch, and secondary bank still reading clearly in the ground.

The site measures roughly 27 metres east to west, though scrub and nettles have taken over the interior and obscured the full north-south dimension. The enclosing bank is built with a notably high stone content, rising about a metre above the fosse, which is the ditch encircling the inner bank. That fosse is wide and flat-bottomed, measuring around 2.7 metres across, with a low outer bank beyond it. The entrance, about 1.8 metres wide and apparently stone-lined, faces east. A field boundary has been cut into the eastern side of the enclosure at some point, and the outer bank has been slightly truncated to the south. Dead wood has accumulated in the fosse and in front of the entrance, and rabbit burrows have worked their way into the inner bank. About 120 metres to the south-west, a standing stone is visible on the hill crest, suggesting the wider landscape around Knockmorris was significant to its early inhabitants well before the ringfort was constructed.