In the northeast nook of the walls is the castle built by the Dukes of Brittany from the 1400s to ensure their ownership of the city, now Saint-Malo’s city hall.
The castle loomed over the city as a reminder of the authority of the dukes, and then the King of France after unification in the 16th century.
The Grand Donjon has the best vistas of Saint-Malo from the platform on its roof.
This building houses a museum about the history of the city and surrounding “Malouin” region, visiting some of the intriguing personalities from this part of France, like the writer Chateaubriand and the explorer Jacques Cartier.