Montana State Highway 37 is a north–south highway located in northern Montana extending south from near Eureka to Libby. The section on the shore of Lake Koocanusa has been given the moniker "The better than sex highway" by participants in the annual Going To The Sun vintage car rally, for its sweeping curves and stunning views.
| 0-mile (0 km) | Begins north of Eureka as a branch off U.S. Route 93 and proceeds west | |
| 6 miles (9.7 km) | Passes by Rexford and turns south following the east shore of Lake Koocanusa | |
| 67 miles (108 km) | Reaches U.S. Route 2 at Libby where it ends |