It begins at Interstate 90 (I-90) in St. Regis and ends at MT 200 near Paradise.

The highway runs along the bank of the Clark Fork River and through Lolo National Forest.

From there, the highway heads to the north and northeast through Lolo National Forest and along the northern bank of the Clark Fork River.

A line of the Montana Rail Link railroad runs parallel to the highway.

The highway ends a couple miles east of Paradise at MT 200.