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, sea-plane landings, and navigation beacons. It was created for or by the Information Division, Office Chief of Air Corps at Engineer Reproduction Plant, U.S. Army, Washington D.C., in 1927 and revised in June 1932. Show less