An actor portraying an expedition member during the crossing of the Bitterroots
On September 11, 1805, the expedition began its 160-mile (260-kilometer) trek through the Bitterroot Range of the Rocky Mountains.
Over 11 days they, in Lewiss words, suffered everything Cold, Hunger, & Fatigue could impart. Starving, they emerged from the mountains near present-day Weippe, Idaho, and into Nez Perce villages.
Photograph by John Livzey