Visit the Château des Ducs de Bretagne
The Château of the Dukes of Brittany is Nantes’ main attraction and a quite incredible historical landmark. Happily, entrance to the courtyard, rampart walk, and moat gardens are free of charge. On the first Sunday of every month (except in July and August, and during major events) you can visit the museum and the temporary exhibitions for free, too. It is a must-see if you are in Nantes, so make it a priority on your agenda.