It is classified as a rath, the Irish term for a ringfort, which was the most common form of rural settlement in early medieval Ireland. These were typically circular enclosures defined by one or more earthen banks and ditches, built to protect a farmstead and its inhabitants, livestock included. Tens of thousands of them survive across Ireland, yet each one occupies a particular patch of ground, shaped by local topography and the decisions of the family who built it, and the one at Monagarraun is no exception.

Ringforts were constructed mainly between the sixth and tenth centuries, though some continued in use into the Norman period and later. The word rath specifically refers to an earthen-banked enclosure, as distinct from a cashel, which used dry-stone walling. Inside a typical rath you might expect to find the remains of a house site, souterrains, which are underground stone-lined passages thought to have served for storage or as places of refuge, and pits or post-holes marking where timber structures once stood. The townland name Monagarraun likely preserves older Irish place-name elements, a common feature in Mayo where the landscape is dense with archaeological remains from prehistoric and early historic periods layered across bog, drumlin, and field.

The Monagarraun rath has not yet been the subject of widely published detailed documentation, and what survives on the ground is best approached with an understanding that Mayo's ringforts vary considerably in their state of preservation. Some survive as clear earthwork circuits, visible as raised banks in pasture or rough ground, while others have been reduced by centuries of farming to little more than a slight rise or a tell-tale curve in a field boundary. The monument is recorded, and its presence in a county so rich in early medieval remains gives it a quiet significance even without a dramatic story attached to it.