Detroit ( dih-TROYT, locally also DEE-troyt) is the largest city in the U.S. state of Michigan. It is also the largest U.S. city on the United States–Canada border, and the seat of government of Wayne County. The City of Detroit had a population of 639,111 at the 2020 census, making it the 27th-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, and the 14th-largest in the United States. Regarded as a major cultural center, Detroit is known for its contributions to music, art, architecture and design, in addition to its historical automotive background. Time named Detroit as one of the fifty World's Greatest Places of 2022 to explore.

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 City of Detroit anchors the third-largest regional economy in the Midwest, behind Chicago and Minneapolis–Saint Paul, and the 16th-largest in the United States. Detroit is best known as the center of the U.S. automobile industry, and the "Big Three" auto manufacturers General Motors, Ford, and Stellantis North America (Chrysler) are all headquartered in Metro Detroit. As of 2007, the Detroit metropolitan area is the number one exporting region among 310 defined metropolitan areas in the United States. The Detroit Metropolitan Airport is among the most important hub airports 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. Both cities will soon be connected by a new bridge currently under construction, the Gordie Howe International Bridge, which will provide a complete freeway-to-freeway link. The new bridge is expected to be open by 2024.

In 1701, Antoine de la Mothe Cadillac and Alphonse de Tonty founded Fort Pontchartrain du Détroit, the future city of Detroit. During the late nineteenth and early twentieth century, it became an important industrial hub at the center of the Great Lakes region. The city's population became the fourth-largest in the nation in 1920, after only New York City, Chicago and Philadelphia, with the expansion of the auto industry in the early 20th century. As Detroit's industrialization took off, the Detroit River became the busiest commercial hub in the world. The strait carried over 65 million tons of shipping commerce through Detroit to locations all over the world each year; the freight throughput was more than three times that of New York and about four times that of London. By the 1940s, the city's population remained the fourth-largest in the country. However, due to industrial restructuring, the loss of jobs in the auto industry, and rapid suburbanization, among other reasons, Detroit entered a state of urban decay and 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 65 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. 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 theaters 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 have increased. An increasingly popular tourist destination, Detroit receives 16 million visitors per year. In 2015, Detroit was named a "City of Design" by UNESCO, the first U.S. city to receive that designation.