A ringfort, or rath, is an enclosed farmstead of the early medieval period, typically circular and defined by one or more earthen banks, and this example at Derrylevick represents one of thousands scattered across the Irish countryside, many surviving in similarly compromised or overlooked condition.

The earthwork is small, roughly D-shaped rather than fully circular, measuring approximately 23 metres north-west to south-east and 20 metres north-east to south-west. Its defining feature is an earthen bank running from the south-east around to the north-west, with a base width of around 4.3 metres narrowing to about 1.8 metres at the top. The internal height of the bank is only about 0.3 metres, while the external face rises to 0.65 metres, modest figures that speak to centuries of erosion and agricultural disturbance. There is no surviving fosse, the ditch that would ordinarily accompany such a bank on the outer side, and no identifiable original entrance. At the north-east, a later field bank cuts across the monument, truncating it and giving it that flattened, D-shaped profile visible on the 1907 map. The drumlin terrain of Monaghan, formed by glacial deposits shaped into elongated hills, would have made this a sheltered and reasonably defensible position for whoever farmed here during the early medieval centuries.