This map depicts the corridor for flight navigation between Cleveland, Ohio, and Chicago, Illinois, including major urban areas, roads, railroads,... Show moreThis map depicts the corridor for flight navigation between Cleveland, Ohio, and Chicago, Illinois, including major urban areas, roads, railroads, etc., and the location of airfields and navigation beacons. It was compiled and produced by the Information Division, Office Chief of Air Corps, at the Engineer Reproduction Plant, U.S. Army, Washington D.C. in 1927, and revised in 1932. Show less