Get wild this Halloween and bring your boys and “ghouls” to trick-or-treat at the wildest neighborhood in town. A spooky (but not too scary) Halloween adventure is planned at this 21st annual HallowZOOeen. Get treats at Goblin Stops, play games and see zoo mascots as you roam the trick-or-treat trail, and don't forget about the haunted train rides. General admission is $7 (or $6 for members), and kids under 2 who are not trick-or-treating will be admitted free.