Purple Heart Trail | ||||
Route information | ||||
Maintained by ITD | ||||
Length | 73.888 mi[1] (118.911 km) | |||
Existed | 1957–present | |||
History | Completed in 1991 | |||
NHS | Entire route | |||
Major junctions | ||||
West end | I-90 at the Washington state line | |||
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East end | I-90 at the Montana state line | |||
Location | ||||
Country | United States | |||
State | Idaho | |||
Counties | Kootenai, Shoshone | |||
Highway system | ||||
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Interstate 90 (I-90) is a transcontinental Interstate Highway that runs east–west across the northern United States. Within the state of Idaho, the freeway travels for 74 miles (119 km) from the Washington border near Spokane to Coeur d'Alene and the panhandle region at the north end of the state. After traveling through the Silver Valley along the Coeur d'Alene River in the Bitterroot Range, I-90 crosses into Montana at Lookout Pass.
I-90 was created by the federal government in 1957, following the general route of U.S. Route 10 (US 10) and the mid-19th century Mullan Road constructed by the U.S. Army. The freeway was constructed in stages between 1960 and 1992.