What I like is that though it's American, pretty much the entire cast is British and it's shot anywhere but there:
Filming locations
Iceland
Morroco: Marrakesh, Ouarzazate
Northern Ireland: Ballymoney, Belfast, Carncastle, Castle Ward, Strangford, Harland and Wolff Paint Hall, Magheramorne Quarry, Shane's Castle, Tollymore Forest Park
Scotland: Doune Castle
Croatia: Dubrovnik
Malta: Dwejra, Mdina, Valletta