Housed in the former International Shoe building, the enormous 600,000 square-foot St. Louis City Museum is more of an adult-sized playground than a standard museum.

Visitors are encouraged to climb on and play in the various exhibits, which include an indoor skate park, salvaged bridges, over 30 different slides, a “Tiny Train Town,” a live circus, enchanted caves and—perhaps the highlight in a museum overflowing with wonders—an exhibit called MonstroCity, which features a castle turret, an adult sized ball pit and two jets suspended high above the ground.

Created by artist Bob Cassilly, the museum has a higher purpose beyond being an adult jungle gym. Built by Cassilly and his team of 20 artists, the City Museum is constructed from materials reclaimed from St. Louis and continues to have a section displaying an “ever-expanding collection of architectural relics.” Don’t miss the ten-story spiral slide that starts at the roof and takes you all the way down to the entrance of the enchanted cave.