It does cost extra, not sure how much. They do close the park but leave most of it open for those with tickets for the event. It is a small group, most rides are left open and they have various Trick-or-Trest stations for the kids to get candy. They have spooky music playing, fall decorations, story tellers, a headless horseman running around and a parade. Took my two nephews last year and they loved it.