Nantes, a city in the Loire Atlantique department located on the Loire River in the Upper Brittany region of western France. Nantes has a long history as a port and industrial center. It’s home to the restored, medieval Château des Ducs de Bretagne, where the Dukes of Brittany once lived. The castle is now a local history museum with multimedia exhibits, as well as a walkway atop its fortified ramparts.