State Route 78 (Arizona–New Mexico) State Route 78 (Arizona–New Mexico) Arizona State Route 78 (SR 78) and New Mexico State Road 78 (NM 78) are a pair of adjoining state highways located in eastern Arizona and western New Mexico linking U.S. Route 191 (US 191) and Arizona State Route 75 near Greenlee County Airport to US 180 northwest of Cliff, New Mexico. It is also known in its Arizona stretch as Mule Creek Road. The western terminus of SR 78 is located at a junction with US 191 and SR 75 at Three Way, Arizona near Greenlee County Airport. The highway heads northeast from this
Former state routes in Arizona from its junction with Interstate 8 in Yuma to the Interstate 8 business loop (which was up until 1977, US 80). The route was turned over to the city of Yuma on April 20, 2007 for maintenance. The road is now Avenue 3E, yet signage for SR 280 remains, including exit signs for Avenue 3E on Interstate 8. SR 280 was the shortest state highway in Arizona, . It existed wholly within the city of Yuma and served the Yuma International Airport. State Route 360 was a state route located in the Phoenix, Arizona area of the United States. From