Interstate Highways are owned and maintained by the Indiana Department of Transportation (INDOT) unless it is a toll road.
  Interstate Highway shields for Interstate 69 and Interstate 465 | |
Interstate Highways highlighted in red | |
| Highway names | |
|---|---|
| Interstates | Interstate X (I-X) |
| US Highways | U.S. Route X (US X) |
| State | State Road X (SR X) |
| System links | |
| |
The system was authorized by the Federal-Aid Highway Act of 1956, which provided federal funds for construction of limited access highways. Indiana's initial set of seven Interstate Highways were announced in September 1957.[1]
Auxiliary Interstates
- ^ Hodenfield, G. K. (September 26, 1957). "New Markers to Dot Super Roads". The Indianapolis News. p. 1. Retrieved November 28, 2021 – via Newspapers.com.
- ^ Federal Highway Administration (January 19, 2012). "Table 1". Route Log and Finder List. Federal Highway Administration.
- ^ Federal Highway Administration (October 31, 2002). "Table 2: Auxiliary Routes of the Dwight D. Eisenhower National System of Interstate and Defense Highways as of October 31, 2002". Route Log and Finder List. Federal Highway Administration. Retrieved July 8, 2007.
- ^ "I-164 Renamed to I-69 by End of Year" (Press release). Indiana Department of Transportation. November 18, 2014. Archived from the original on March 3, 2017. Retrieved March 2, 2017.
- ^ a b c Federal Highway Administration (December 31, 2016). "Table 2". Route Log and Finder List. Federal Highway Administration. Retrieved March 14, 2017.