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 266 Arizona State Route 266 State Route 266 (SR 266) is a highway in Graham County, Arizona that runs from its junction with US 191 south of Safford to Fort Grant. It is an east–west route. The eastern terminus of SR 266 is located on US 191 south of Safford. The highway heads southwest from this intersection before curving towards the west. It briefly curves towards the northwest before curving back towards the west and arriving in Fort Grant. The highway continues towards the west to its western terminus in Bonita. SR 266 has a spur route that heads north from