Interstate 11 (I-11) is an Interstate Highway that currently runs for on a predominantly northwest–southeast alignment in the US state of Nevada, running concurrently with US 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. An exact alignment for I-11 has yet to be determined outside of these sections; however, a number of corridor alternatives have been identified for further study and refinement. 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. However, extensions of the corridor to the north toward Reno and to the south toward Nogales have since been approved by the 2015 Fixing America's Surface Transportation Act. The proposed 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. However, I-17 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. The subsequent plan to extend the Interstate north of Las Vegas to Reno would, if constructed, put that 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. Route description Arizona The southern terminus of the freeway would be at I-19 Business Loop in Nogales, Arizona, concurrent with that of I-19 proper, or follow State Route 189 (SR 189) from its intersection with I-19 to the Mariposa Port of Entry where it continues south as Federal Highway 15D, creating a Nogales, Arizona–Nogales, Sonora metro area bypass for high-density CANAMEX Corridor