Other professional and semi-professional teams in Washington include: DC Defenders (XFL), Old Glory DC (Major League Rugby), the Washington Kastles (World TeamTennis); the Washington D.C. Slayers (USA Rugby League); the Baltimore Washington Eagles (U.S. Australian Football League); the D.C. Divas (Independent Women's Football League); and the Potomac Athletic Club RFC (Rugby Super League). The William H.G. FitzGerald Tennis Center in Rock Creek Park hosts the Citi Open. Washington is also home to two major annual marathon races: the Marine Corps Marathon, which is held every autumn, and the Rock 'n' Roll USA Marathon held in the spring. The Marine Corps Marathon began in 1976 and is sometimes called "The People's Marathon" because it is the largest marathon that does not offer prize money to participants.