This is a rath, the most common type of early medieval monument in Ireland, essentially a defended homestead built from earth rather than stone, typically consisting of a raised circular bank and an accompanying fosse, or ditch, enclosing a domestic space. What makes the example at Rathordan quietly interesting is how well it has survived in spite of everything pressing against it.

The enclosure measures approximately 35 metres in diameter, and its earthen bank is substantial by any measure, running about six metres wide at the base and narrowing to two metres at the top, with an external height of roughly 2.25 metres. That combination of width and height suggests a monument that was built to impress as much as to protect. The outer fosse is equally considerable where it can be seen, stretching nearly nine and a half metres wide and three metres across at its base. The western sector of the ditch has been cut away by the farmyard that now abuts it, and dense vegetation obscures whether it survives to the north-west and south-east, though it remains visible to the south and south-west. The bank itself is described as very well preserved, which, given the encroachment of trees, ivy, and agricultural activity on all sides, is something of an achievement across however many centuries it has been sitting here.