U.S. Route 66 in Arizona

U.S. Route 66 (US 66, Route 66) also known as the Will Rogers Highway, was a major United States Numbered Highway in the state of Arizona from November 11, 1926, to June 26, 1985. US 66 covered a total of 385.20 miles (619.92 km) through Arizona. The highway ran from west to east, starting in Needles, California, through Kingman and Seligman to the New Mexico state line. Nationally, US 66 ran from Santa Monica, California, to Chicago, Illinois. In its height of popularity, US 66 was one of the most popular highways in the state of Arizona, sometimes carrying over one million cars a year.

In the early years, US 66 had to compete with other major U.S. Highways for construction and improvement funding. The highway also played an important role during the Dust Bowl as a means for refugees (also known as "Okies") to escape the ruined farmlands of the Great Plains and migrate to California. Experiences of these refugees traveling through Arizona were largely detailed in John Steinbeck's novel, The Grapes of Wrath, and the 1940 movie adaption that followed. During the mid-20th century, the highway became a tourist destination, spawning the existence of several new motels, restaurants and other road-side businesses and attractions.

With the introduction of Interstate 40 (I-40), US 66 began declining considerably, with some of the towns along the highway becoming ghost towns. Following the completion of I-40, US 66 was completely decommissioned by the Arizona Department of Transportation (ADOT) in 1984, then retired nationwide the following year. Significant portions of the old highway remain, such as State Route 66 (SR 66) between Kingman and the Yavapai–Coconino county line east of Peach Springs. Since 1987, other sections have been designated as Historic Route 66, which is both an Arizona Historic Road and a National Scenic Byway.