Detroit /dɨˈtrɔɪt/ is the most populous city in the U.S. state of Michigan, and is also the seat of Wayne County, the most populous county in the state and the largest city on the United States-Canada border. It is a primary business, cultural, financial and transportation center in the Metro Detroit area, a region of 5.2 million people, and serves as a major port on the Detroit River connecting the Great Lakes system to the Saint Lawrence Seaway. It was founded on July 24, 1701, by the French explorer and adventurer Antoine Laumet de La Mothe, sieur de Cadillac.The Detroit area emerged as a significant metropolitan region within the United States as construction of a regional freeway system was completed in the 1950s and 1960s. With these commuting ties allowing social and economic integration across a larger area, the Detroit name sometimes refers to the three-county Urban Area (population 3,734,090, area of 1,337 square miles, as of the 2010 United States Census), the six-countyMetropolitan Statistical Area, or the nine-county Combined Statistical Area. The Detroit–Windsor area, a commercial link straddling the Canada–U.S. border, has a total population of about 5,700,000. The Detroit metropolitan region currently holds roughly one-half of the state's population.Known as the world's traditional automotive center, "Detroit" is a metonym for the American automobile industry and an important source of popular music legacies celebrated by the city's two familiar nicknames, the Motor City and Motown. Other nicknames arose in the 20th century, including City of Champions beginning in the 1930s for its successes in individual and team sport, The D, Hockeytown, Rock City, and The 313. Detroit's auto industry was an important element of the American "Arsenal of Democracy" supporting the Allied powers during World War II.Between 2000 and 2010 the city's population fell by 25 percent, changing its ranking from the nation's 10th largest city to 18th. In 2010, the city had a population of 713,777, more than a 60 percent drop down from a peak population of over 1.8 million at the 1950 census, indicating a serious and long-running decline of Detroit's economic strength. Commensurate with the shift of population and jobs to its suburbs or other states, the city has had to adjust its role within the larger metropolitan area. Downtown Detroit has seen an increased role as an entertainment hub in the 21st century, with the opening of three casinos, new stadiums, and a riverfront revitalization project. However, many neighborhoods remain distressed.The state governor declared a financial emergency in March 2013, appointing an emergency manager. On July 18, 2013, Detroit filed the largest municipal bankruptcy case in U.S. history. It was declared bankrupt by U.S. judge Stephen Rhodes on December 3, who cited its $18.5 billion debt and declared that negotiations with its thousands of creditors were unfeasible.