US 160 enters New Mexico from Arizona on a two-lane highway that heads northeast through the arid, rolling plains of the Navajo section of the Colorado Plateau.

Approximately 0.3 miles (480 m) into the state is an intersection with New Mexico State Road 597 (NM 597), a short highway that leads to the Four Corners Monument, which lies on the quadripoint of Arizona, New Mexico, Colorado, and Utah.

[2] US 160 continues to the northeast and descends into the San Juan River valley, but the highway crosses into Colorado before reaching the river.

[4] A proposal to renumber the highway to US 160 was deferred by the American Association of State Highway Officials (AASHO; now AASHTO) in 1969 and approved the following year.

[5][6] The entire route is in San Juan County.