Six Flags Great America brings new thrills to Fright Fest September 21, 2012 GURNEE, Ill. – Six Flags Great America kicks off its 22nd season of Fright Fest with new haunts and more scares than ever before. GURNEE, Ill. – Six Flags Great America kicks off its 22nd season of Fright Fest with new haunts and more scares than ever before. Starting September 29 and running weekends throughout October, the theme park transforms into a 100-acre, fog-filled land of shadows, ghosts and ghouls that offers thrills by day and fright by night. Fright Fest, the area’s premier Halloween event, returns this season with five haunted attractions, eight horrific scare zones, eight hair-raising shows and nearly 200 monsters throughout the park. Guests can also enjoy all of their favorite rides with an eerie makeover.