Flint is a city in the U.S. state of Michigan, located along the Flint River, 66 miles northwest of Detroit. According to the 2010 census, Flint has a population of 102,434, making it the seventh largest city in Michigan. Flint is the county seat of Genesee County in the Flint/Tri-Cities region of Michigan. Genesee County largely comprises the entirety of Flint's metropolitan area, the fourth largest metropolitan area in Michigan with a population of 425,790 in 2010. Flint is best known as the birthplace of General Motors (GM), and the Flint Sit-Down Strike of 1936–37 that played a vital role in the formation of the United Auto Workers. Flint is also home to the headquarters of Citizens Republic Bancorp.