The United Center is an indoor arena on the Near West Side of Chicago, Illinois. It is home to the Chicago Bulls of the National Basketball Association (NBA) and the Chicago Blackhawks of the National Hockey League (NHL). It is named for its corporate sponsor United Airlines. With a capacity of nearly 21,000, the United Center is the largest arena by capacity in the NBA, and second largest arena by capacity in the NHL. It also has a seating capacity of 23,500 for concerts.
https://en.wikipedia.org/wiki/United_Center