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 10
Interstate 10 (I-10) is the southernmost cross-country Interstate Highway in the American Interstate Highway System. It stretches from the Pacific Ocean at California State Route 1 (Pacific Coast Highway) in Santa Monica, California, to I-95 in Jacksonville, Florida. Major cities connected by I-10 include (from west to east) Los Angeles, Phoenix, Tucson, El Paso, San Antonio, Houston, Baton Rouge, New Orleans, and Jacksonville. This freeway is part of the originally planned Interstate Highway network that was laid out in 1956, and its last section was completed in 1990. I-10 is the fourth-longest Interstate Highway in the United States, following I-90, I-80, and I-40. About one-third of its length is within the state of Texas, where the freeway spans the state at its widest breadth.