Through careful planning and hundreds if not thousands of hours of three-dimensional printing, the Chicago Architecture Foundation has reproduced the city of Chicago as a 25-foot by 35-foot model. The designers were inspired by similar models in Beijing and Shanghai, and used a process called stereolithography to duplicate more than 1,000 Windy City buildings. Stereolitholography uses a laser to precisely sculpt hair-thin layers of acrylic into 3D form. The Tribune Tower took about 40 hours to recreate this way, and some buildings require 70 hours. When the buildings are done, they’re arranged on trays that are brought individually into the site of the model. The point of all this? Simply to marvel at what’s regarded as an excellent piece of urban design. If you’re in Chicago through September 20, check it out at the foundation’s Michigan Avenue headquarters. [Chicago Tribune]