| This article is part of the highway renumbering series. | |
|---|---|
| Alabama | 1928, 1957 |
| Arkansas | 1926 |
| California | 1964 |
| Colorado | 1953, 1968 |
| Connecticut | 1932, 1963 |
| Florida | 1945 |
| Indiana | 1926 |
| Iowa | 1926, 1969 |
| Louisiana | 1955 |
| Maine | 1933 |
| Massachusetts | 1933 |
| Minnesota | 1934 |
| Missouri | 1926 |
| Montana | 1932 |
| Nebraska | 1926 |
| Nevada | 1976 |
| New Jersey | 1927, 1953 |
| New Mexico | 1988 |
| New York | 1927, 1930 |
| North Carolina | 1934, 1937, 1940, 1961 |
| Ohio | 1923, 1927, 1962 |
| Pennsylvania | 1928, 1961 |
| Puerto Rico | 1953 |
| South Carolina | 1928, 1937 |
| South Dakota | 1927, 1975 |
| Tennessee | 1983 |
| Texas | 1939 |
| Utah | 1962, 1977 |
| Virginia | 1923, 1928, 1933, 1940, 1958 |
| Washington | 1964 |
| Wisconsin | 1926 |
| Wyoming | 1927 |
On January 1, 1969, the Iowa State Highway Commission, now known as the Iowa Department of Transportation, renumbered several state highways. The changes to the highway system fixed a number of issues: creating continuous route numbers across state lines, removing duplicate route numbers where they were unnecessary, and extending route numbers in some locations. Twenty-six sections of highway were assigned new route numbers, duplicate route numbers were removed on eleven sections, and one route number was extended to another section.[1]