U.S. Route 90
U.S. Route 90 (US 90) is an east–west United States highway. Despite the "0" in its route number, US 90 never was a full coast-to-coast route; it has always ended at Van Horn, Texas with the exception of a short-lived northward extension to US 62/US 180 near Pine Springs, Texas which lasted less than a year, and the signs on that segment were changed to Texas State Highway 54, traveling from Interstate 10 (I-10) at exit 140A and heading to its northern terminus at US 62/US 180.
Interstate 90 in Idaho
The freeway turns east in the town of Wallace, also served by its own business route, and travels to the north of downtown on an elevated viaduct cut into a nearby hill. At the east end of Wallace, I-90 intersects SH-4, which connects to the ghost town of Burke. The highway continues along the south side of the river and Trail of the Coeur d'Alenes as it ascends further into the mountains and meanders around hills and gulches. The trail ends at the town of Mullan, named for road-building U.S. Army captain John Mullan and home to a business route, and I-90 continues east along the Northern Pacific Trail. The freeway travels uphill from the river along a southern ridge and passes a scenic viewpoint commemorating the 1903 Willow Creek avalanche. I-90 then turns south and leaves Idaho at Lookout Pass, elevated above sea level and located adjacent to the Lookout Pass Ski and Recreation Area. The freeway continues into Montana and travels through the cities of Butte, Bozeman, and Billings.