The Illinois Department of Transportation (IDOT) was formed to promote safe, efficient, and cost-effective transportation in Illinois. It was preceded by the Illinois Department of Public Works and Buildings. IDOT maintains the public roadways, provides funding for transportation projects, and administers funding to localities within the state. It has responsibility for highways, bridges, airports, public transit, and freight and passenger rail systems.
The images in this online collection have been scanned from negatives and prints in the IDOT Chicago Traffic Photograph Collection housed in the Special Collections Department at the University of Illinois at Chicago. The Collection contains approximately 2,300 images from Chicago transportation surveys and projects. Many of the prints appear to have been made for the Chicago Park District Engineering Section. They document transportation in Chicago from the 1920s to the 1950s, and depict intersections, subways and underpasses, signs, bridges and viaducts, snow removal, pedestrians, and other features of traffic in the city.