This map depicts the corridor for flight navigation between San Francisco, California, and Medford, Oregon, including major urban areas, roads,... Show moreThis map depicts the corridor for flight navigation between San Francisco, California, and Medford, Oregon, including major urban areas, roads, railroads, etc., and the location of airfields, sea-plane 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 1927, and revised in 1930. Show less