A ringfort, or rath, is a roughly circular enclosure built in earth or stone, most commonly during the early medieval period in Ireland, and used as a defended farmstead for a single family or small community. This one at Beagh is subcircular in plan, measuring approximately 55 metres from northwest to southeast and 50 metres from northeast to southwest, and what sets it apart structurally is the internal stone-facing of its enclosing bank, a detail that points to some care in its original construction.

The bank is best preserved along its northeastern and western sections, where the stonework can still be read against the grass. Along the eastern side, from roughly east-northeast to east, the enclosing element shifts from a built bank to a natural or cut scarp, suggesting the builders made use of whatever the local topography offered. A gap at the southern side, though modern in its present form, may correspond to the original entrance point, which in ringforts of this type was often positioned to face south or southeast. A road now circles the monument from the south-southwest around through the west to the northwest, giving the site an oddly framed quality, a prehistoric enclosure with a modern lane for a companion.