Interstate 40 in Arizona Interstate 40 in Arizona Interstate 40 (I-40) is an east–west Interstate Highway that has a section in the U.S. state of Arizona, connecting sections in California and New Mexico. The section throughout Arizona is also known as the Purple Heart Trail. It enters Arizona from the west at a crossing of the Colorado River southwest of Kingman. It travels eastward across the northern portion of the state connecting the cities of Kingman, Ash Fork, Williams, Flagstaff, Winslow, and Holbrook. I-40 continues into New Mexico, heading to Albuquerque. The highway has major junctions with U.S. Route 93 (US 93) — the
Arizona State Route 66 line, much of US 66 has been replaced with I-40. Various stretches of the old highway exist as frontage roads and business loops of I-40. In 1984, US 66 was officially removed from the state highway system of Arizona. Most of the old highway had been replaced by I-40, but the portion between Kingman and Seligman where I-40 followed a new alignment to the south became SR 66. In 1990, the state turned over the easternmost of SR 66 (known as Crookton Rd) to Yavapai County for maintenance. Arizona State Route 66 State Route 66 (SR 66) is a surface