This sub-rectangular earthwork measures roughly 53 metres northwest to southeast and 46 metres northeast to southwest, its boundaries still clearly defined despite centuries of weathering. The southwestern and northwestern sides are protected by an earthen bank standing 1.75 metres high, whilst the northeastern and southeastern edges take advantage of the natural defences provided by the steep scarp, which drops nearly 10 metres at its highest point.

The site’s defensive features reveal the careful planning of its medieval builders. A fosse, or defensive ditch, runs along the southwestern side, reaching depths of 1.25 metres and accompanied by a counterscarp bank half a metre in height. There may be another overgrown fosse on the northeastern side, though vegetation makes this difficult to confirm. The interior of the site is slightly raised and relatively level towards the northwest, gradually sloping down towards the southeast where the land meets the scarp edge.

At the southeastern edge of the scarp, an overgrown mound hints at what might be the remains of a structure, possibly a dwelling or defensive tower that once stood within this fortified enclosure. These moated sites were typically built by Anglo-Norman settlers or Gaelicised Norman families between the 13th and 15th centuries, serving as fortified farmsteads that combined residential, agricultural, and defensive functions. The Mawbeg East site represents one of many such earthworks scattered across the Irish countryside, each telling a story of medieval life when security and status were literally built into the landscape.