History

Arizona’s oldest freeway is still pretty young. Here’s how it started

Although Black Canyon Freeway has changed since the 1950s, this iconic freeway was a key part of tourism and travel in the Grand Canyon State.

aerial black and white photo of Interstate 17 freeway
An aerial photo of Interstate 17 in 1967. Also known as the Black Canyon Freeway, I-17 was the first freeway in Phoenix when it opened in 1950. It now connects Interstate 10 in Phoenix to Interstate 40 in Flagstaff. (Provided by Maricopa Association of Governments via Reuters Connect)

Although Arizona gained its statehood in 1912, developing its freeways took a little bit more time. 

The United States was changing, and modern industrialization and automobile transportation was key during that era. With Arizona statehood brought great change, but improving the quality of roads was not one of them.

MORE: How did metro Phoenix streets get their names? Here’s the story behind 46 roads

Due to a lack of funds as a young state, Arizona highways were created quite modestly with the labor of prisoners, taxpayer dollars and materials like dirt. Arizona’s automobile registration rose from 1,852 in 1912 to 12,124 in 1916, but there was still not a single road paved with asphalt or concrete. Rather roads were covered in crushed rock.

It wasn’t until 1957 that Arizona’s first freeway was finished, the first step in transforming the state into the busy network of freeways we are more familiar with today.

Arizona’s oldest freeway 

Arizona’s oldest freeway is Black Canyon Freeway. Freeway construction started in 1950 and finished seven years later, bringing Arizona up to date with automobile transit in the U.S.

The original Black Canyon Road was a Native American trail that later became a U.S. Army route from Fort Whipple, outside Prescott, to Fort McDowell, east of Phoenix, according to the Arizona Department of Transportation. It was later used as a stage coach line.

After Congress approved a major spending bill to build 40,000 miles of interstate highways, the freeway began to take shape. 

The Black Canyon Freeway initially started with an interchange at Grand Avenue that opened in 1957. Just a few years later, it reached Northern Avenue, according to ADOT. It just kept expanding from there. By 1964, the Black Canyon Freeway section of I-17 connected to the Carefree Highway; it was extended on to Flagstaff in 1978.

Although Black Canyon Freeway has changed since the 1950s, this iconic freeway was a key part of tourism and travel in the Grand Canyon State.

Reporting by Paige Moore, Arizona Republic

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