Ringforts are fortified settlements that are typical of the 5th and 6th century AD in Ireland. They are known as ráth, caiseal, cathair and dún in the early Irish sources. A ráth (anglicised rath), was made of earth, caiseal (northwestern Ireland, anglicised cashel) and cathair (southwestern Ireland) were built of stone. A dun is a more prestigious site, the seat of some kind of ruler, the term is applied to promontory forts as well.
There is no sure indication of continuity of this form of fortification from the Iron Age.
A recently excavated ringfort is Lios-na-gCon, West Cork, Ireland