Local blog Chicagoist recently posted about a Flickr set that UIC posted of the Chicago Aerial Photo Services Collection. You can check out the Flickr set, or explore the entire digital collection hosted by UIC. They describe the project:
The Chicago Aerial Photo Services (CAPS) collection has a number of aerial photographs from 1929 through the late 1940s. Primarily the photographs are of the Chicago area though there are some images from other areas of the state. They provide detailed images of both urban areas as well as countryside that would become suburbs in the future.
UIC’s digital collections also hosts several other collections pertaining to Chicago architecture, including the C. William Brubaker Collection of mid-to-late 20th century color photographs. For more information, visit the Chicago Aerial Photo Services (CAPS) collection or the C. William Brubaker Collection.