This map depicts the corridor for flight navigation between Louisville, Kentucky, Cincinnati, Ohio, and St. Louis, Missouri, including major urban... Show moreThis map depicts the corridor for flight navigation between Louisville, Kentucky, Cincinnati, Ohio, and St. Louis, Missouri, including major urban areas, roads, railroads, etc., and the location of airfields, seaplane landings, and navigation beacons. It was compiled and produced by the Engineer Reproduction Plant, Corps of Engineers under the direction of the Airways Section, Office Chief of Air Corps in 1925. Show less