Roads and freeways in metropolitan Phoenix
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 as of 2005.
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. 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.
Overview
Freeways fall under the auspices of the Arizona Department of Transportation. Phoenix ranks first in the nation in the quality of its urban freeways, and the state as a whole ranks first in the nation in the quality of bridges. While being the fifth most populous city in the nation, Phoenix's freeways do not suffer from the same type of congestion seen in other large cities. In fact, in a recent study, there is not a single stretch of freeway in Phoenix ranked in the 100 worst freeways for either congestion or unreliability.Opposition and Local Tax
There was significant local opposition in the 1960s and 1970s to expansion of the freeway system. 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 designations as opposed to Interstate designations.Consequently, Phoenix is the largest city in the United States to have at least two Interstate Highways, but no three-digit Interstates. However, the majority of these existing state route and loop freeways still adhere mostly to Interstate Highway standards. Additionally, federal statute provides that free roads of any funding source are eligible for Interstate designation; only toll roads built strictly with federal funds are disqualified. All of Phoenix's state route and loop freeways are free roads, making it possible for them to still be assigned potential three-digit Interstate designations in the future, although no such plans are currently in place.
Interstate Highways and U.S. Routes
Interstate 10 (Papago and Maricopa Freeways)
enters the metropolitan area from the west in Buckeye and proceeds through the West Valley cities of Goodyear, Avondale, and Tolleson; it interchanges with the Loop 303 in Goodyear and the northbound Loop 101 in Tolleson. Following the Loop 101 interchange, I-10 reaches the western city limits of Phoenix. It meets the Loop 202 South Mountain Freeway between 59th and 51st avenues.As it approaches downtown Phoenix, I-10 has the first of two interchanges with Interstate 17, a four-level symmetrical stack interchange known locally as The Stack. I-10 and I-17 box in downtown Phoenix. The alignment of the Papago Freeway north of downtown was highly controversial—the first elevated design, ten stories high, triggered a successful freeway revolt. It was the last segment of I-10 to be completed nationwide, opening to traffic in August 1990. It features the Deck Park Tunnel—in actuality, 13 side-by-side bridges supporting Margaret T. Hance Park. I-10 turns south at the Mini Stack, which connects to State Route 51 to the north and Loop 202 to the east. South of the Mini Stack, I-10 provides the western access to Phoenix Sky Harbor International Airport.
I-10 merges with I-17 at the Split, the latter interstate's southern terminus, and shifts onto the alignment known as the Maricopa Freeway. It proceeds east and south over the Salt River; interchanges with SR 143, the primary eastern access to the airport, as it enters Tempe; and turns due south at the Broadway Curve. Several miles later, it interchanges with US 60. The highway serves Tempe, Guadalupe, Chandler, and the Ahwatukee neighborhood of Phoenix before meeting the Loop 202 for a third time on the border with the Gila River Indian Community.
Interstate 17 (Black Canyon and Maricopa Freeways)
enters the Valley from the north as the Black Canyon Freeway, in the New River and Anthem area. It has a partially completed interchange with Loop 303 and a four-level interchange with Loop 101. It then continues directly southward on the 27th and 25th Avenue alignments in northern Phoenix, passing the former Metrocenter mall site as it heads directly for downtown. This segment is the oldest freeway in the state. Another four-level stack awaits I-17 when it meets Interstate 10 immediately northwest of downtown at The Stack. The highway bends east at the Durango Curve and changes designations from the Black Canyon Freeway to the Maricopa Freeway, bounding downtown Phoenix to the west and south before merging with I-10 at the Split.U.S. Route 60 (Superstition Freeway)
While US 60 is co-signed with I-10 and I-17 through central Phoenix, it becomes a separate freeway in its own right on an east-west alignment between Baseline Road and Southern Avenue. Known as the Superstition Freeway, this alignment serves major East Valley cities including Tempe, Mesa, Gilbert, and Apache Junction. There are two interchanges, with the Loop 101 and Loop 202. The latter is known as the SuperRedTan Interchange because it links the Superstition, Red Mountain, and Santan freeways.Loops
Loop 101 (Agua Fria, Pima, and Price Freeways)
is the oldest of Phoenix's three beltways, opening in segments between 1988 and 2002. It follows an inverted U shape encircling Phoenix from the north to the southeast, as the Agua Fria Freeway west of I-17; the Pima Freeway from I-17 to the Loop 202 Red Mountain Freeway; and the Price Freeway south to its terminus at the Loop 202 Santan Freeway in Chandler. Along the way, it serves Glendale, Peoria, north Phoenix, Scottsdale, the Salt River Pima-Maricopa Indian Community, and Tempe.Loop 202 (Red Mountain, Santan, and South Mountain Freeways)
serves as the outer belt for much of the southeastern and southwestern Valley. The first section of the Red Mountain Freeway, known then as the East Papago Freeway as it continues the east-west alignment of I-10, opened on August 27, 1990; the full planned alignment was not complete until the South Mountain Freeway opened in December 2019. Starting and ending in the city of Phoenix, it serves Mesa, Gilbert, and Chandler along the way.Construction of the South Mountain Freeway segment, envisioned in the 1980s, was postponed for years by fights over land use with the Gila River Indian Community, which was unwilling to have the freeway built on its land.
Loop 303 (Bob Stump Memorial Freeway)
The Loop 303 is the second ring road for the Valley's northwest quadrant, extending from just south of I-10 in Goodyear to a temporary interchange with I-17 in far north Phoenix and serving outer Northwest Valley communities including Surprise, Sun City and Sun City West, and northern Peoria. It has become a major corridor for warehouse uses, attracted by the relatively low travel time to the Southern California market.Other controlled-access highways
State Route 24 (Gateway Freeway)
The Gateway Freeway serves far southeast Mesa, including its namesake Phoenix-Mesa Gateway Airport, and rapidly growing areas in Queen Creek and San Tan Valley. The first segment, an interchange with Loop 202 and ramps to Ellsworth Road, opened in 2014. To meet growing demand for a regional transportation link, an interim second phase, featuring an overpass over Ellsworth Road and continuing as a divided highway with at-grade intersections out to Ironwood Drive, was completed in 2022. Future plans include converting the Ellsworth Road-Ironwood Drive segment to a full freeway, as well as extending the freeway east to meet with the future Pinal North-South Freeway near San Tan Valley, as well as US-60 near Gold Canyon.State Route 51 (Piestewa Freeway)
The Piestewa Freeway begins at the Mini Stack interchange with I-10 and Loop 202 and proceeds north through the city of Phoenix towards Piestewa Peak, formerly known as Squaw Peak. After passing near Paradise Valley, SR 51 reaches its northern terminus at Loop 101.This freeway was formerly known as the Squaw Peak Parkway, but since "Squaw" is regarded as a derogatory term for Native American women, the Arizona Board of Geographic and Historic Names rechristened the mountain "Piestewa" Peak after Lori Piestewa, a Native American woman who died in the conflict with Iraq. The name change was controversial, with some residents still referring to both the freeway and the landmark peak as Squaw Peak.