Interstate 11

Interstate 11 (I-11) is an Interstate Highway that currently runs for 22.6 miles (36.4 km) on a predominantly northwest–southeast alignment in the U.S. state of Nevada, running concurrently with U.S. Route 93 (US 93) between the Arizona state line and Henderson. The freeway is tentatively planned to run from Nogales, Arizona, to the vicinity of Reno, Nevada, generally following the current routes of I-19, I-10, US 93, and US 95. Planners anticipate upgrading two existing highway segments to carry future I-11: US 93 in Arizona from Wickenburg to the Nevada state line on the Mike O'Callaghan–Pat Tillman Memorial Bridge over the Colorado River and US 95 in Nevada from the Las Vegas Valley to Tonopah. In 2024, officials will begin replacing I-515 signs in Las Vegas with I-11 signs and adding I-11 signs on US 95 north of Downtown Las Vegas, which will extend I-11 northward about 30.5 miles (49.1 km). An extension of the Interstate northward along US 95 to Mercury, Nevada, is planned after that. An exact alignment for I-11 has yet to be determined outside of these sections; a number of corridor alternatives, however, have been identified for further study and refinement. The building of I-11 in Arizona is also facing local opposition from conservation groups.

As originally proposed in the 2012 Moving Ahead for Progress in the 21st Century Act, the highway would run only from Casa Grande, Arizona, to Las Vegas. This was to provide a Las Vegas–Phoenix freeway link. Extensions of the corridor to the north toward Reno and to the south toward Nogales, however, have since been approved by the 2015 Fixing America's Surface Transportation Act (FAST Act).

The numbering of this highway does not currently fit within the usual conventions of the existing Interstate Highway grid as it is east of I-15 and should therefore have a number greater than 15. I-17, however, was already built to the east of the I-11 alignment in Arizona, making it impossible to fit this freeway's Interstate number into the national grid and remain within the traditional numbering convention. I-11 being extended along US 95 through Las Vegas and crossing over I-15 will remedy this situation since it will put a portion of I-11 west of I-15 and thus in line with the national grid numbering conventions.

The 80th session of the Nevada Legislature passed a bill designating the entire route of I-11 in the state as the Purple Heart Highway, which went into effect on July 1, 2019.