This is a rath, the Irish term for a ringfort, a type of enclosed farmstead built predominantly during the early medieval period, roughly between the fifth and twelfth centuries. Thousands of them survive across Ireland in varying states of preservation, and this one at Cloonlara sits on elevated ground with particularly open views to the south-west, across a wide stretch of pasture and bog.

The enclosure is broadly oval, measuring roughly 45.5 metres east to west and 51 metres north to south. The earthen bank that defines it survives best on the north-north-east to south-west arc, where it still stands about 1.1 metres high on its outer face, though elsewhere it has been worn down to a low scarp. Centuries of practical farming have left their marks. A section of the bank at the north-east has been pressed into service as a field boundary, and another stretch on the south-east to south has had a later field fence built against its outer face. Two gaps of about ten metres each interrupt the circuit: one to the north-east and east, which may reflect a widening of an original entrance, and one to the north, cut open to allow tractor access for silage cutting in the interior. The inside of the rath is slightly domed, rising gently to a low central point before sloping back towards the bank. The eastern half of the perimeter is fringed with hawthorn and blackthorn, which gives that arc of the old enclosure a more visually defined edge than the rest. A building that appeared immediately outside the north-east of the rath on the 1916 Ordnance Survey six-inch map has since been removed, leaving the grassy interior largely undisturbed.