Cathair

Ringforts, ring forts or ring fortresses are circular fortified settlements that were mostly built during the Bronze age up to about the year 1000. They are found in Northern Europe, especially in Ireland. There are also many in South Wales and in Cornwall, where they are called rounds. Ringforts come in many sizes and may be made of stone or earth. Earthen ringforts would have been marked by a circular rampart (a bank and ditch), often with a stakewall. Both stone and earthen ringforts would generally have had at least one building inside.

In Irish language sources they are known by a number of names: ráth (anglicised rath), lios (anglicised lis; cognate with Cornish lis),caiseal (anglicised cashel), cathair (anglicised caher or cahir; cognate with Welsh caer, Cornish and Breton ker) and dún (anglicised dun or doon; cognate with Welsh and Cornish din). The ráth and lios was an earthen ringfort; the ráth being the enclosing bank and the lios being the open space within. The caiseal and cathair was a stone ringfort. The term dún was usually used for any stronghold of importance, which may or may not be ring-shaped.

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