Detroit (link=no) is the largest and most populous city in the U.S. state of Michigan, the largest U.S. city on the United States–Canada border, and the seat of Wayne County. The municipality of Detroit had a 2018 estimated population of 672,662, making it the 23rd-most populous city in the United States. The metropolitan area, known as Metro Detroit, is home to 4.3 million people, making it the second-largest in the Midwest after the Chicago metropolitan area. Regarded as a major cultural center, Detroit is known for its contributions to music and as a repository for art, architecture and design. Detroit is a major port on the Detroit River, one of the four major straits that connect the Great Lakes system to the Saint Lawrence Seaway. The Detroit Metropolitan Airport is among the most important hubs in the United States. The City of Detroit anchors the second-largest regional economy in the Midwest, behind Chicago and ahead of Minneapolis–Saint Paul, and the 13th-largest in the United States. Detroit and its neighboring Canadian city Windsor are connected through a highway tunnel, railway tunnel, and the Ambassador Bridge, which is the second busiest international crossing in North America, after San Diego–Tijuana. Detroit is best known as the center of the U.S. automobile industry, and the "Big Three" auto manufacturers General Motors, Ford, and Fiat Chrysler are all headquartered in Metro Detroit. In 1701, Antoine de la Mothe Cadillac founded Fort Pontchartrain du Détroit, the future city of Detroit. During the 19th century, it became an important industrial hub at the center of the Great Lakes region. The city became the 4th-largest in the nation in 1920, after only New York City, Chicago, and Philadelphia with the influence of the booming auto industry. With expansion of the auto industry in the early 20th century, the city and its suburbs experienced rapid growth, and by the 1940s, the city had become the fourth-largest in the country. However, due to industrial restructuring, the loss of jobs in the auto industry, and rapid suburbanization, Detroit lost considerable population from the late 20th century to the present. Since reaching a peak of 1.85 million at the 1950 census, Detroit's population has declined by more than 60 percent. In 2013, Detroit became the largest U.S. city to file for bankruptcy, which it successfully exited in December 2014, when the city government regained control of Detroit's finances. Detroit's diverse culture has had both local and international influence, particularly in music, with the city giving rise to the genres of Motown and techno, and playing an important role in the development of jazz, hip-hop, rock, and punk music. The rapid growth of Detroit in its boom years resulted in a globally unique stock of architectural monuments and historic places. Since the 2000s conservation efforts have managed to save many architectural pieces and achieved several large-scale revitalizations, including the restoration of several historic theatres and entertainment venues, high-rise renovations, new sports stadiums, and a riverfront revitalization project. More recently, the population of Downtown Detroit, Midtown Detroit, and various other neighborhoods has increased. An increasingly popular tourist destination, Detroit receives 19 million visitors per year. In 2015, Detroit was named a "City of Design" by UNESCO, the first U.S. city to receive that designation.