Explore Chicago, Illinois, USA Chicago, on Lake Michigan in Illinois, is among the largest cities in the U.S. Famed for its bold architecture, it has a skyline punctuated by skyscrapers such as the iconic John Hancock Center, 1,451-ft. Willis Tower (formerly the Sears Tower) and the neo-Gothic Tribune Tower. The city is also renowned for its museums, including the Art Institute of Chicago with its noted Impressionist and Post-Impressionist works. Things To Do What Does Chicago Have to Offer? View the links below to see what Chicago has to offer! Check out these 32 free things to do in Chicago First time in Chicago? This Guide is for you!