The Northwest Passage Scenic Byway follows the Lewis and Clark expedition’s quest for a watercourse through the Rocky Mountains connecting the Missouri and Columbia rivers and parallels the explorers' journey through the ancestral Nez Perce homeland in 1805–1806. Designated by the Federal Highway Administration as an All-American Road, it is recognized for nationally significant cultural, natural, and scenic qualities. The 202-mile route stretches from Lewiston to Lolo Pass on U.S. Highway 12 and from Kooskia to Grangeville on Idaho Highway 13, following the Nez Perce and Lewis and Clark National Historic Trails along two wild and scenic rivers, with parks, waysides, and kiosks providing information along the way.