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.
Massachusetts Route 28
The original form of Route 28 was as a New England interstate route established in 1922 to run from Buzzards Bay to New Hampshire. The route itself was overlaid on several early turnpike roads constructed in the early 19th century. Except for an extension into Cape Cod in 1926, the overall highway layout and routing is largely unchanged from its original design. Route 28 has been realigned in several places when newer, higher quality roads were built. At a length of nearly , Route 28 is the longest state-numbered highway in Massachusetts, and the second-longest highway, behind U.S. Route 20.