Many historians consider Lemhi Pass the most important site along the Lewis and Clark National Historic Trail. It was here that the dream of the Northwest Passage died and the expedition began its passage through the Rocky Mountains with horses acquired from the Lemhi Shoshone. Stands of fir and pine trees and mountain meadows look much the same today. The Lewis and Clark Backcountry Byway takes travelers along a single lane road with steep grades. A memorial near the pass commemorates Sacajawea, the expedition's Shoshone interpreter.