The main goal of my and my parents' trip to Rennes was to visit the rich Musée des Beaux-Arts ("Museum of Fine Arts"). Our guidebook said that the museum was closed on Tuesdays, so we went there on a Monday. When we saw the palace housing the museum (called Palais des Musées), we noticed that there was no queue and when we arrived at the gate, a guard informed us that the closing day of the museum was Monday. We were very angry with the publisher of our guidebook (Touring Club Italiano), which had just been published!
So, you'd better inform yourself well before visiting the museum. Check the site below.
First get information about the tides before going to Mont St Michel. Otherwise you might lose your car! Or you can't leave the city for a while... When the tide comes up, the parking lot and the way to Mont St Michel runs under water. It's impossible to get through then.