Six Flags - Great America Six Flags “Great America” is fun, fast, and exciting! Visit one of America’s greatest theme parks right here in Chicago.Six Flags Great America is located midway between Chicago and Milwaukee. This park was built for the entire family to enjoy. Six Flags Great America is the Midwest's premier theme park. Enjoy over 11 world class roller coasters including the Megacoaster, Vertical Velocity, Déjà vu, and more!  Great America also features a variety of shops and shows to compliment the thrilling roller coasters. Six Flags Great America 542 N Route 21 Gurnee, IL 60031 (847) 249-4636