The interior of this enclosure sits visibly higher than the surrounding ground, a subtle but telling detail that speaks to centuries of accumulated occupation and undisturbed soil. A gap three metres wide in the eastern side of the bank marks what was almost certainly the original entrance, and an external fosse, a shallow defensive ditch, still survives to a depth of around 1.2 metres around the perimeter.

This is a rath, the most common type of ringfort in Ireland, constructed from earthen banks rather than stone and typically dating from the early medieval period, roughly the fifth to the twelfth centuries. Raths served as enclosed farmsteads, the bank and fosse providing security for a family, their livestock, and their outbuildings. The Rathmorgan example measures approximately 44 metres east to west and 37 metres north to south, making it a reasonably substantial example of the form. The western and northern sections of the interior bank are the best preserved, giving a clearer sense of the original scale and solidity of the enclosure. The place-name itself carries the evidence: the Irish word ráth, meaning a circular earthen fort or enclosure, is embedded in Rathmorgan, a reminder that local communities have recognised and named these features in the landscape for a very long time.