Grianan is located on a small hill about three miles outside of Derry~Londonderry. It stands sentinel like over looking the city. The structure is a ‘cashel’ ie a stone ring fort. There are many examples of the type along the west coast of Ireland but this is one of the best. The stone fort is in fact a product of the last period of development at the site, and if you stand on the battlements you can just about make out the two great lines of earthen embankments which encircle the place and formed its original defences. The structure is reputed to date to the Iron Age.
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