Donegal Castle is a castle situated in the centre of Donegal town, County Donegal in the northwest of Ireland. Originating from a Viking fortress in1159,The elder Sir Hugh O’Donnell, wealthy chief of the O’Donnell clan, built the castle in 1474. For most of the last two centuries, the majority of the buildings lay in ruins but the castle was almost fully restored in the late 1990s , info wiki , photo by andrew mcmillan