This is a rath, the Irish term for a ringfort, the kind of enclosed farmstead that was common across Ireland during the early medieval period, roughly between the fifth and twelfth centuries. Thousands survive in various states of preservation, but many have been levelled by centuries of ploughing or land improvement. This one has held its shape with some tenacity.

The enclosure measures approximately 22 metres north to south and 23 metres east to west, making it a fairly modest example of its type. The defining feature is the scarp, a steep earthen bank, which rises to 3.55 metres and is accompanied on its south-eastern to southern arc by an external fosse, a defensive ditch, surviving to a depth of around 0.45 metres. The original entrance faces roughly south-south-west, a detail that points to deliberate planning rather than accident. Locally, according to O'Brien writing in 1970, the site has long been known as Lisbeg, a name derived from the Irish lios beag, meaning simply "small fort". The name is modest, practical, and probably accurate; this was not a great fortified stronghold but a protected enclosure for a farming family and their livestock, the kind of place where ordinary early medieval life was conducted at a remove from the wider landscape.