A selection of some of the most beautiful castles in County Donegal, Ireland. www.facebook.com/DiscoverUlster Castle ruins can be spotted in many areas of the county, including: Burt Castle, (near Letterkenny) Carrickabraghy Castle, (near Clonmany) Doe Castle, (Cresslough) Donegal Castle (Donegal Town) Glenveagh Castle (near Letterkenny) Inch Castle (inch Island, Inishowen)) Lough Eske Castle (near Donegal Town) McSwyne Castle (Near Killybegs) Mongavlin Castle ((near Lifford) O'Doherty Keep (Buncrana) Raphoe Castle (Raphoe Town) Termon McGrath Castle (Pettigo)