There's free admission to Millennium Park, the playful heart of the city. It shines with whimsical public art, both permanent and temporary exhibits, and it hosts a mixture of free and ticketed activities and events. From the band shell to the artworks on display, here are the top things to see in Millennium Park.

The second-largest art museum in the country, the Art Institute houses a treasure trove from around the globe. The collection of impressionist and postimpressionist paintings is second only to those in France, and the number of surrealist works is tremendous. Wander the endless marble and glass corridors, and rooms stuffed…