Roads and freeways in metropolitan Phoenix

Map of freeways and major highways in the Phoenix area

•      Interstate Highways
•      U.S. Highways
•      State highways
•      State loops
•      Other freeways/highways

The metropolitan area of Phoenix in the U.S. state of Arizona contains one of the nation's largest and fastest-growing freeway systems, with over 1,405 lane miles (2,261 km) as of 2005 (this was before construction on the Loop 303 started).^[1]

Due to the lack of any form of mass transit besides bus prior to 2008, the Phoenix Metropolitan Area has remained a very automobile-dependent city, with its first freeway opening in 1958—a year preceding most cities' first freeway openings. Coupled with the explosive growth of the region and adequate funding, the result is one of the nation's most expansive freeway networks.

The backbone of Phoenix's freeway system is composed of three major freeways—Interstate 10, Interstate 17, and U.S. Route 60. Interstate 10, being a transcontinental route between California and Florida, is the most heavily traveled freeway in the Valley of the Sun. Interstate 17 runs down the center of Arizona, connecting Phoenix with Sedona, Prescott, Flagstaff and the Grand Canyon. U.S. Route 60 spans most of the country, but is only a freeway for a few short stints, one of them being in the East Valley. West of Phoenix, it shuttles travelers to cities such as Wickenburg, Kingman and Las Vegas (by way of a connection in Wickenburg with U.S. Route 93). In addition to these three freeways, three beltways, Routes 101, 202, and 303 loop around Phoenix, the East Valley, and the West Valley, respectively. State Route 51 connects Downtown with the northern reaches of the city, and Arizona State Route 143 is a distributor for Phoenix Sky Harbor International Airport.

There was significant local opposition in the 1960s and 1970s to expansion of the freeway system.^[2] Because of this, by the time public opinion began to favor freeway expansion in the 1980s and 1990s, Phoenix freeways had to be funded primarily by local sales tax dollars rather than diminishing sources of federal money; newer freeways were, and continue to be, given state route designation as opposed to Interstate designation. Primarily due to this, Phoenix is the largest city in the United States to have at least two Interstate Highways, but no three-digit Interstates.^[3]