United States. Public Roads Administration.1 map in 8 sectionsScale 1:250,000. Approximately 1 inch to 4 milesModified polyconic projectionW 96°37′--W 90°07′/N 43°30′--N 40°07′JPEGui:sheetmaps_164engThe AdministrationPublicIowa transportation map: Highways, railroads, canals, air lanes, and dredged channels, 1941MapsIowa1940-1950University of Iowa