Tucked into pasture on a south-east-facing slope just to the west of St Peter's church, the site contains not only the earthworks of the fort itself but, within its interior, a burial ground and the remains of what may be a church. That combination, a prehistoric or early medieval enclosure later repurposed for Christian burial and possibly worship, is a pattern found elsewhere in Ireland but never loses its strangeness: the living built a defended space, and generations later the dead were laid inside it.

A rath, as this type of ringfort is known, is an enclosure formed by one or more circular earthen banks, typically used in early medieval Ireland as a farmstead or residence for a family of some local standing. The Curragh example measures 32 metres north to south, enclosed by an earthen bank that still stands roughly a metre high on its interior face and slightly less on the exterior. Beyond the bank, a fosse, essentially a defensive ditch, survives, though it has softened over the centuries into a gentle slope rather than the sharp-cut trench it would once have presented. The north-north-west to north-east arc of this fosse is particularly overgrown. One detail worth noting is the way the interior has been deliberately raised on its south-east side to level out the natural fall of the hillslope, a small but telling piece of engineering that speaks to the care taken in the original construction.