1 Best Sight in Duluth, Minnesota

Great Lakes Aquarium

America's only all-freshwater aquarium, on the harbor at the foot of Fifth Avenue West, has been open since 2000. In addition to fish native to Lakes Superior and Erie, it houses—all under one roof—a natural-history center, science center, and cultural exhibits covering regional topics like Great Lakes shipwrecks, management of water systems in national forests, and the invasion of zebra mussels. Classroom space hosts educational programming for children and adults, and typically sells out during the summer months. There's also a café and a gift shop.