Six Flags Great America in Gurnee, Illinois, is the state's largest amusement park and one of North America's most visited seasonal parks. Opened in 1976 as Marriott’s Great America, it grew from an early-1970s plan for history-themed parks tied to the U.S. bicentennial. Architect Randall Duell organized it with a circular “Duell loop” of themed lands that emphasized an idealized Americana. After Six Flags bought the park in 1984, it expanded with major roller coasters such as Shockwave, Iron Wolf, and Batman: The Ride. With 11 themed sections, a long operating history, and several historically recognized coasters, it remains a major regional attraction.