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 decertified. It was instead extended to US 66. The road up to the dam site still exists today as a county route. It was the only spur route of State Route 72. In 1962, this route became part of State Route 95. State Route 173 was a north-south state highway in north-central Arizona, that connected Show Low and McNary Jct., now known as Hon Dah. The route and travels along part of the Mogollon Rim. It first appeared on a state map in 1946 and became part of State Route 260 in 1972. This route was a spur of State