The Grianan of Aileach, near Derry in the Inishowen Peninsula of Co. Donegal, was the ancient hilltop fortress of the McLaughlin and O'Neill Kings of Ulster before it was destroyed by Murtough O'Brien in 1101 A.D. and subsequently abandoned. The view overlooks Loughs Swilly and Foyle from the top of Grianan Mountain . It was partially restored in 1870.