Iowa. Highway CommissionShows roads in various states of construction: paved, gravel, graded, or not yet built.; Road mileage: Primary roads - 6,615 miles. Secondary roads - 97,466.0 miles.; Printed on blue paper with Iowa Bond watermark.16 x 23 Centimeters, on sheet 22 x 28 CentimetersJPEGUMN_ALMA:9976878106301701engIowa Highway Commission (Place of publication not identified)PublicMap of Iowa primary road system : work completed or under contract Dec. 1, 1922MapsIowaUniversity of Minnesota