Thanks to the nutrient-rich outflow of water from the Skagit River, beautiful Penn Cove’s famous mussels grow full-sized in record time and are harvested young, making them impossibly firm, fat, and sweet. This annual festival, which bills itself as a celebration of all things “bold, briny, and blue,” features boat tours of the Penn Cove Mussel Farm, a mussel eating contest, cooking demonstrations with local chefs, a waterfront beer garden, and the main event: a tasting competition with restaurants from all over Coupeville vying to have their mussel chowder declared the finest in town.