One of the busiest times of year at many Jellystone Park locations are the weeks leading up to Halloween. That’s when the Yogi Bear-themed parks offer a variety of fall and pre-Halloween activities ranging from making caramel apples and scarecrows to costume, campsite, and pumpkin-decorating contests to trick-or-treating. Some locations even offer zombie hunts, haunted hayrides, haunted houses, and haunted trails.