Milwaukee ( mil-WAW-kee) is the most populous city in the U.S. state of Wisconsin and the county seat of Milwaukee County. With a population of 577,222 at the 2020 census, Milwaukee is the 31st-most populous city in the United States and the fifth-most populous city in the Midwest. It is the central city of the Milwaukee metropolitan area, the 40th-most populous metro area in the U.S. with 1.57 million residents. Milwaukee is an ethnically and culturally diverse city. However, it continues to be one of the most racially segregated cities, largely as a result of early-20th-century redlining. Its history was heavily influenced by German immigrants in the 19th century, and it continues to be a center for German-American culture, specifically becoming well known for its brewing industry. In recent years, Milwaukee has undergone several development projects. Major additions to the city since the turn of the 21st century include the Wisconsin Center, American Family Field, The Hop streetcar system, an expansion to the Milwaukee Art Museum, Milwaukee Repertory Theater, the Bradley Symphony Center, and Discovery World, as well as major renovations to the UW–Milwaukee Panther Arena. Fiserv Forum opened in late 2018, and hosts sporting events and concerts. Milwaukee is categorized as a "Gamma minus" city by the Globalization and World Cities Research Network, with a regional GDP of over $102 billion in 2020. Since 1968, Milwaukee has been home to Summerfest, a large music festival. Milwaukee is home to the Fortune 500 companies of Northwestern Mutual, Fiserv, WEC Energy Group, Rockwell Automation, and Harley-Davidson. It is also home to several colleges, including Marquette University, the Medical College of Wisconsin, Milwaukee School of Engineering, and University of Wisconsin–Milwaukee. The city is represented in two of the four major professional sports leagues—the Bucks of the NBA and the Brewers of MLB.