Duluth, Minnesota Lakes Waterway and the Saint Lawrence Seaway. Duluth forms a metropolitan area with neighboring Superior, Wisconsin, called the Twin Ports. The cities share the Duluth–Superior harbor and together are the Great Lakes' largest port, transporting coal, iron ore (taconite), and grain. A tourist destination for the Midwest, Duluth features the United States' only all-freshwater aquarium, the Great Lakes Aquarium; the Aerial Lift Bridge, which spans the Duluth Ship Canal into the Duluth–Superior Harbor; and Minnesota Point (known locally as Park Point), the world's longest freshwater baymouth bar, spanning . The city is also the starting point for vehicle trips along
Duluth, Minnesota along the Duluth waterfront. The Great Lakes Aquarium is in the Duluth Waterfront Park. A freshwater aquarium, it features animals and habitats found in the Great Lakes Basin and other freshwater ecosystems such as the Amazon River. The aquarium houses 205 different species of fish, birds, reptiles, amphibians and mammals. It is one of the few aquariums in the United States to focus on freshwater exhibits. The 16-acre Lake Superior Zoo offers year-round recreational activities and features animals from around the world, including Amur tigers, snow leopards, African lions, brown bears, kangaroos, and gray wolves, plus a variety of birds,