Arizona State Route 78

Arizona and New Mexico Route 78
Route 78 highlighted in red
Route information
Maintained by ADOT & NMDOT
Length:	34.68 mi (55.81 km) 19.47 mi (31.33 km) in Arizona 15.213 mi (24.483 km) in New Mexico
Existed:	1938-1959 – present
Major junctions
West end:	US 191 / SR 75 in Three Way, AZ
East end:	US 180 near Cliff, NM
Highway system
Arizona Highways Interstate U.S. State Unconstructed Former State Roads in New Mexico Interstate US State Minor Scenic ← SR 77 AZ SR 79 → ← NM 77 NM NM 80 →

Arizona State Route 78 and New Mexico State Road 78 (SR 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 intersection along Mule Creek Road. There are a few hairpin turns along this stretch of highway as it follows the surrounding terrain. State Road 78 heads eastward through desert, passing through the community of Mule Creek, New Mexico. The road continues eastward until terminating at U.S. Route 180 northwest of Cliff, New Mexico.