SH 151's western terminus is at SH 172 in Ignacio, and the eastern terminus is at U.S. Route 160 (US 160) east of Chimney Rock.

From there, the road proceeds generally eastward with a southern arc past Allison and through Arboles.

The route then turns to the northeast passing near Navajo State Park and across the Piedra River.

25.7 mi (41.4 km) from its western end at Ignacio, SH 151 enters San Juan National Forest through which it continues to its eastern endpoint at US 160 roughly six miles east of Chimney Rock.

Media related to Colorado State Highway 151 at Wikimedia Commons