Duluth is a seaport city in the U.S. state of Minnesota and the county seat of St. Louis County. The city had a total population of 86,918 in the 2000 census and the metropolitan census including outer suburbs and villages was estimated to be roughly 184,000. At the westernmost point on the north shore of Lake Superior, Duluth is linked to the Atlantic Ocean 2,300 miles (3,700 km) away via the Great Lakes and Erie Canal/New York State Barge Canal or Saint Lawrence Seaway passages and is the Atlantic Ocean's westernmost deep-water port.

Duluth forms a metropolitan area with Superior, Wisconsin. Called the Twin Ports, these two cities share the Duluth-Superior Harbor and together are one of the most important ports on the Great Lakes, shipping coal, iron ore (taconite), and grain. As a tourist destination for the Midwest, Duluth features America's only all-freshwater aquarium, the Great Lakes Aquarium, the Aerial Lift Bridge which spans the short canal into Duluth's harbor, "Park Point", the world's second longest freshwater sandbar, spanning 6 miles, and is a launching point for the North Shore.

The city is named for Daniel Greysolon, Sieur du Lhut, the first known European explorer of the area.