Interstate 17 (I-17) is a north–south Interstate Highway located entirely within the US state of Arizona. I-17's southern terminus lies in Phoenix, at I-10/US 60 and its northern terminus is in Flagstaff, at I-40.
The northern portion of the B Line of the Valley Metro Rail system runs over a bridge of I-17 from Mountain View Road to Metro Parkway, serving one station at Metro Parkway.
I-17 ends at I-40 and SR 89A (Milton Road) in Flagstaff.
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File:I-10 and I-17 stack, PHX.jpg|"The Stack", intersection of I-10 and I-17. Looking north up I-17, downtown Phoenix.
File:Interstate 17 southern terminus in Phoenix.jpg|Southern terminus at I-10 in Phoenix
File:Sedona Red Rocks from I-17.jpg|View of the Red Rocks of Sedona from I-17, just south of Munds Park
File:Interstate 17, Arizona.jpg|I-17 near Flagstaff
File:I-40 in Arizona towards LA.jpg|Northern terminus at I-40 as seen from I-40 in Flagstaff
</gallery>
History
The I-17 corridor roughly follows the first stagecoach route through the Black Canyon, established in 1878 between Cañon (now Black Canyon City) and Prescott. A later highway through White Spar from Wickenburg to Yarnell was improved in 1925 and incorporated into US 89 in 1926.
In 1936, SR 69 was established as a state route from Phoenix north to Prescott. The road was completed by 1940 to Prescott. In 1954, a new route north to Flagstaff was established as SR 79. In May 1956, the Black Canyon Highway from Phoenix to Flagstaff was completed, It was incorporated into the new Interstate Highway System, established by the federal government later that year, and designated as part of I-17. The final section of I-17, near Camp Verde and Montezuma Castle, began construction in February 1977 and opened to traffic in August 1978.
In 1993, officials in Arizona proposed an extension of I-17 to connect with I-15 in Utah,, but plans were ultimately scrapped due to environmental concerns.
The existing interchange with Happy Valley Road in Phoenix was converted to a diverging diamond interchange (DDI). The project was finished in the fall of 2020.
Due to increasing weekend traffic on I-17 between the Phoenix area and northern Arizona, primarily between Phoenix in the south, and Sedona, Flagstaff, and the Grand Canyon in the north, ADOT started plans to widen a section of four-lane freeway between Anthem and the Sunset Point Rest Area in 2018. In 2021, the design was chosen, with a standard third general-purpose lane set to be added in both directions between Anthem and Black Canyon City, but due to the mountainous topography north of Black Canyon City to Sunset Point, two flex lanes will be added in a separate carriageway next to the existing southbound lanes. The lanes will be allocated depending on whichever direction has the most traffic, generally this will be northbound traffic from Monday through Saturday, and southbound traffic on Sundays. A combination of six different safety systems (vehicle arresting barriers, automated arm gates, concrete barriers, steel gates, dynamic messaging signs, and cameras) will control access to these lanes. Construction began in 2022 and in May 2025, the additional lanes from Anthem to Black Canyon City opened. The flex lanes are scheduled to be completed by the end of 2025.
Exit list
Former business route
State Business Route 17 (also known as SR 17 Bus.) was a former business loop of I-17 that served the west side of Black Canyon City, Arizona. SR 17 Bus. followed Old Black Canyon Highway (formerly SR 69 before I-17 replaced most of the route between Phoenix and Cordes Junction) from exit 242 south of town at a diamond interchange to another diamond interchange at exit 244 north of town. The business route was subsequently transferred from state to local maintenance and because of ADOT's policy of not signing business loops on nonstate maintained roadways, the route was decommissioned in 2011.
Major intersections<br/>
See also
- Roads and freeways in metropolitan Phoenix
- Interstate 19
References
External links
- I-17 at ArizonaRoads.com
- Google Maps I-17