An Grainan Aileach [Greenan Hill, Ringfort] ,is in beautiful County Donegal Ireland. The fort is situated on an 800ft hill so commands amazing views over 3 counties, Donegal,Tyrone and County Derry/Londonderry.The location was believed to have been occupied as early as the late Bronze age.The fort was built up to maybe 4 times it's height now in the 8th century.It was ruined in the 11th century by the King of Munster with the arrival of the Normans. A must see for visitors to the county.