Detroit ( dih-TROYT, locally also DEE-troyt) is the most populous city in the U.S. state of Michigan. It is the largest U.S. city on the Canadian border and the county seat of Wayne County. Detroit had a population of 639,111 at the 2020 census, making it the 26th-most populous city in the United States. The Metro Detroit area, home to 4.3 million people, is the second-largest in the Midwest after the Chicago metropolitan area and the 14th-largest in the United States. A significant cultural center, Detroit is known for its contributions to music, art, architecture and design, in addition to its historical automotive background. In 1701, Royal French explorers Antoine de la Mothe Cadillac (1758-1730), and Alphonse de Tonty (1659-1727), founded Fort Pontchartrain du Détroit. During the late 19th and early 20th century, it became an important industrial hub at the center of the Great Lakes region in the Midwestern United States. The city's population rose to be the fourth-largest in the nation by 1920, after larger New York City, Chicago, and Philadelphia, with the expansion of the automotive industry in the early 20th century. One of its main features, the Detroit River, became the busiest commercial hub in the world—carrying over 65 million tons of shipping commerce each year. In the mid-20th century, Detroit entered a state of urban decay which has continued to the present, as a result of industrial restructuring, the loss of jobs in the auto industry, and rapid suburbanization. Since reaching a peak of 1.85 million at the 1950 census, Detroit's population has declined by more than 65 percent. In 2013, Detroit became the largest U.S. city to file for bankruptcy, but successfully exited in December 2014. Detroit is a port on the Detroit River, one of the four major straits that connect the Great Lakes system to the St. Lawrence Seaway. The city anchors the third-largest regional economy in the Midwest and the 16th-largest in the United States. It is also best known as the center of the U.S. automotive industry, and the "Big Three" auto manufacturers—General Motors, Ford, and Stellantis North America (Chrysler)—are all headquartered in Metro Detroit. It houses the Detroit Metropolitan Airport, one of the most important hub airports in the United States. Detroit and its neighboring Canadian city Windsor constitute the second-busiest international crossing in North America, after San Diego–Tijuana. Detroit's culture is marked with diversity, having both local and international influences. Detroit gave rise to the music genres of Motown and techno, and also played an important role in the development of jazz, hip-hop, rock, and punk. A globally unique stock of architectural monuments and historic places was the result of the city's rapid growth in its boom years. Since the 2000s, conservation efforts have managed to save many architectural pieces and achieve several large-scale revitalizations, including the restoration of several historic theaters and entertainment venues, high-rise renovations, new sports stadiums, and a riverfront revitalization project. Detroit is an increasingly popular tourist destination which caters to about 16 million visitors per year. In 2015, Detroit was given a name called "City of Design" by UNESCO, the first and only U.S. city to receive that designation.