Located in St. Louis, Missouri, the City Museum is an urban playground of 600 000 square meters, built on the ruins of an old shoe factory of 10 storey. The sculptor and artist Bob Cassilly is the founder of this project on which he has been working since 1997, after years of renovation and construction. Although Cassilly passed away in 2011, the project keeps going on and extending with new attractions, thanks to a group of 20 artists from the Cassilly Crew.