List of state highways in Iowa
State highways in the U.S. state of Iowa are owned and maintained by the Iowa Department of Transportation .
State highways
References
^ 2012 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation . January 1, 2012. Retrieved November 6, 2013 .
^ 2002 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation. January 1, 2002. Retrieved September 3, 2019 .
^ a b c d e f g h "U.S. Road Markers Soon to Replace Familiar Primary Road Signs on U.S. System in Iowa". Service Bulletin Oct–Nov–Dec 1925 . XIII (10–11–12). Iowa State Highway Commission : 3. 1925.
^ a b c d e f g h i j k l m 1938 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa State Highway Commission . September 26, 1938. Retrieved September 13, 2019 .
^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af ag ah ai aj 1965 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa State Highway Commission. June 1966. Retrieved September 13, 2019 .
^ a b c d e f g h i j 1956 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa State Highway Commission . May 1957. Retrieved September 14, 2019 .
^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac 1978 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation. December 31, 1978. Retrieved September 13, 2019 .
^ a b c d e f g h i 1941 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa State Highway Commission . April 30, 1942. Retrieved September 14, 2019 .
^ a b c d e f g h 1996 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation. August 1997. Retrieved September 3, 2019 .
^ a b c d e f g h i j k 1934 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa State Highway Commission . March 25, 1935. Retrieved September 13, 2019 .
^ a b c d e f g h 1968 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa State Highway Commission. March 1970. Retrieved September 13, 2019 .
^ a b c d e f g h i j k l m 1984 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation. August 1985. Retrieved September 3, 2019 .
^ a b c d e f g h i j 1970 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa State Highway Commission. July 1971. Retrieved September 13, 2019 .
^ a b c d 1982 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation. December 31, 1982. Retrieved September 3, 2019 .
^ a b c d e f g h i 1980 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation. December 31, 1980. Retrieved September 13, 2019 .
^ a b c d e f g h i j k l m 1959 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa State Highway Commission . June 1960. Retrieved September 14, 2019 .
^ a b c d e f g h i j k l m n o p 1988 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation. January 1, 1988. Retrieved September 3, 2019 .
^ a b c d e f g h 1974 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa State Highway Commission. May 1, 1976. Retrieved September 13, 2019 .
^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa 1962 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa State Highway Commission. May 1963. Retrieved September 13, 2019 .
^ a b c d e f 1986 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation. 1987. Retrieved September 3, 2019 .
^ a b c d 1953 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa State Highway Commission . August 1954. Retrieved September 14, 2019 .
^ a b c d e f g 1972 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa State Highway Commission. April 1973. Retrieved September 13, 2019 .
^ a b 1951 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa State Highway Commission . January 1, 1951. Retrieved September 14, 2019 .
^ a b c d 1976 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation. December 31, 1976. Retrieved September 12, 2019 .
^ a b c d e f g h i 2000 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation. August 2001. Retrieved September 3, 2019 .
^ a b c d 1990 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation. 1991. Retrieved September 3, 2019 .
^ a b c d 2006 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation. January 1, 2006. Retrieved September 3, 2019 .
^ 2003 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation. January 1, 2003. Retrieved September 3, 2019 .
^ a b c d 1998 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation. 1999. Retrieved September 3, 2019 .
^ "Primary Route Descriptions – Unsigned Iowa 374 in Jasper County" . Iowa Department of Transportation. Retrieved September 3, 2019 .
^ 1949 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa State Highway Commission . January 1951. Retrieved September 14, 2019 .
^ 2004 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation. January 1, 2004. Retrieved September 3, 2019 .
^ 2008 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation. January 1, 2008. Retrieved September 3, 2019 .
^ "Primary Route Descriptions – Iowa 475 in Monona County" . Iowa Department of Transportation. Retrieved September 3, 2019 .
^ "Official Description Change: Unsigned Iowa 915, Polk County" . Iowa Department of Transportation . July 24, 1996.
^ a b c d e 1994 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation. August 1995. Retrieved September 3, 2019 .
^ a b c d e f g h i 1992 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation. 1993. Retrieved September 7, 2019 .