The rath at Mullawornia, sitting at the base of a south-facing slope in County Longford, departs from that norm. Its footprint is D-shaped, with a notably straight south-western side, giving it an irregular geometry that still reads clearly in the landscape even after considerable damage to its southern and western edges.

A ringfort, or rath, was typically an enclosed farmstead of the early medieval period, its bank and ditch serving as much as a marker of social status as a defensive barrier. At Mullawornia, that enclosing boundary survives in places as a scarp rising between half a metre and one and a half metres, with an external fosse, a ditch, running alongside it. The fosse is relatively modest, recorded at roughly 1.8 metres wide and 0.2 metres deep, though erosion and agricultural activity will have reduced it from whatever its original profile was. The monument is legible from the northern and north-eastern sides, where the scarp is still intact, but the southern and western portions were lost to the construction of farm buildings that, though now disused, did enough damage to obscure any trace of the original entrance. A further curiosity sits inside the enclosure: a bank with its own accompanying fosse running from the inner face of the north-eastern perimeter toward the centre of the interior. Its origin appears to be modern rather than early medieval, though its precise purpose is not recorded, and it now sits as a later intrusion within an already fragmentary site.