Interstate 10 in Arizona 2013. The remainder of the old US 80 section was rebuilt to interstate standards, with completion in 2014. East of Tucson, I‑10 parallels and in some cases overlies old US 80 to Benson, and was originally co-signed as US 80 and SR 86. The section of I-10 from Valencia Road to Rita Road was the first construction project in the state of Arizona funded by the Federal Aid Highway Act of 1956. Construction began in 1957 and was completed in 1960. From Benson, the Interstate follows the Southern Pacific mainline east through Willcox and Bowie to New Mexico, rather than
Arizona State Route 93 being extended from Kingman by way of US 66 through Ash Fork. A new US 193 was proposed from Phoenix through Sacaton and Casa Grande to Picacho. At the time, US 89 served the road between Ash Fork and Phoenix, while State Route 87, State Route 187 and State Route 84 ran between Sacaton and Picacho through Casa Grande (of which only SR 87 still traverses today). Upon hearing of the proposed extensions, citizens of Wickenburg, Arizona, Wikieup and Aguila protested to have US 93 run through their towns instead. The protest was considered and the Arizona Highway Department changed