Duluth, United States offers 23 beaches perfect for sunbathing, surfing, swimming, and more. Duluth, Minnesota, United States, is known for the Aerial Lift Bridge and the scenic North Shore of Lake Superior. The best time to travel to Duluth, United States, is in late summer, around August, when the average air temperature is about 70°F (21°C) and the water temperature in Lake Superior is approximately 60°F (16°C). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!