Here are a few ideas for things to do when it rains:
Entertainment: Cinéma Le Select in Granville, media libraries (Granville, Donville-les-Bains, Bréhal, Saint-Pair-sur-Mer, La Haye-Pesnel…), Bowling “Boules et Billes”, Thalasso et Spa Marin Prévithal, Rejouets, etc.
Discover: Le Roc des Curiosités museum-aquarium, Richard Anacréon Museum of Modern Art, Christian Dior Museum, Abbaye de la Lucerne, Faïencerie du Mont-Saint-Michel, located in Saint-Pair-sur-Mer, various art galleries, notably at Rue des Juifs, in Granville, Château de Chanteloup, etc.
Taste: L’écume des Falaises in Jullouville or la Fée d’Orge in Bréhal, the various terroir stores to be found in the area (un Poil Gourmand, les Délices de Camille, …)
Be active: Royal Kids, Centre Aquatique l’Hippocampe, some equestrian centers have indoor parks.