List of Interstate Highways in Utah
The Interstate Highways in Utah are maintained by the Utah Department of Transportation (UDOT). The Interstate Highway System is a nationwide system with only a small portion of these routes entering Utah. Originally, the State Road Commission of Utah, created on March 23, 1909 was responsible for maintenance, but these duties were rolled into the new UDOT in 1975. There are of Interstates within the state. The longest is Interstate 15 (I-15) at and the shortest is I-215 at . One unique former route is Interstate 415, which was never signed as such, and was only used as a temporary designation for the eastern portion of what is now the Interstate 215 belt loop around Salt Lake City.
Interstate 275 (Ohio–Indiana–Kentucky)
Interstate 275 (I-275) is an loop in Ohio, Indiana, and Kentucky that forms a complete beltway around the Cincinnati area, and includes a part in a state (Indiana) not entered by the parent route. It had been the only auxiliary interstate that enters three states, but that changed in July 2018 when I-295 in Delaware and New Jersey was extended into Pennsylvania. It is the longest loop interstate highway in the United States, and it encloses an area of over 250,000 acres. For a short distance in northwest Hamilton County it overlaps with I-74 and U.S. Highway 52 (US 52).