Back in the late 1800s through to, probably, the 1930s, Ajo Way went by a different name: Robles Road. Robles Road was a dirt path that went west from Tucson through Robles Pass near Cat Mountain, and led to the Robles Ranch at Robles Junction, also called Three Points. The road was named for Bernabe S. Robles. The name Robles Road does show up on the official Map of Pima County, 1893, opens a new window.
The article, "Street Smarts: Rancher was one of early Tucson's largest land owners, opens a new window details the life of Robles and his family history.
In 1935 a contract was awarded to Borderland Construction Co. to begin construction of the Ajo-Tucson Highway beginning
approximately 5 miles west of Tucson. Today, the roadway west of I-19 or Mission Road (depending on which street map you look at) Ajo Way becomes Ajo Highway or Arizona State Route 86.
"Road Projects Under Construction in Arizona." Arizona Highways. April 1935, Page 20.
Leighton, David. "Street Smarts: Rancher was one of early Tucson's largest land owners, opens a new window." Arizona Daily Star. September 8, 2014.
Historic Arizona County Road Maps, opens a new window | Arizona Memory Project
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