The highway runs north–south through Jackson and Grand counties in north central Colorado.

South of Walden, it crosses the southern end of North Park along the valley of the Illinois River, a tributary of the Michigan.

It passes the unincorporated community of Rand, then ascends into the mountains and crosses the continental divide at Willow Creek Pass (elevation 9621 ft), one of the lowest crossings of the continental divide in Colorado.

On the south side of the pass it descends the sparsely populated valley of Willow Creek into Middle Park.

It terminates at its southern end at U.S. Highway 40 two miles (3.2 km) west of Granby.