Fright Fest at Six Flags Great America
Time Out says
If you really want to scream, head to Six Flags Great America where you can ride roller coasters in the dark and visit six haunted houses. Escape evil clowns, delve into the gates of hell, and explore a cursed manor. As you wander the park you’ll encounter demons, zombie lumberjacks, nightmarish fairy tales, and creepy circus performers. You can add to the frightful fun by snacking on Halloween-themed treats, watching a nightly parade and catching shows featuring live music, dancing and illusions.