Visiting the northern Brittany coast sounds completely delightful — Mont St. Michel, Paimpol, the pink granite coast — but several recent articles have revealed serious problems with Brittany’s northern beaches, especially in the Côtes-d’Armor department. Algae, washing up on shore and decaying, has made some beaches perilous:

Harmless while in water, the algae form dangerous gases — notably hydrogen sulfide, with its characteristic rotten-egg smell — when they wash up on land and decay.… Read the rest