Emerald coast is the name given to the Breton coast between Cancale and le Cap Fréhel because of the colour of the water… To discover the Emerald coast, the towns of Cancale and St-Malo in Ille-et-Vilaine and the towns of Fréhel and St-Cast-le-Guildo in the Côtes-d’Armor offer you a large choice of various campsites in each town. There is a five star campsite in St-Cast-le-Guildo.