The Lewis and Clark Expedition Route: From the Missouri to the Pacific

The Lewis and Clark Expedition, officially known as the Corps of Discovery, was a joint venture led by Captain Meriwether Lewis and Second Lieutenant William Clark. Between 1804 and 1806, the expedition charted a path from the Mississippi River to the Pacific Ocean and back.

The journey began near St. Louis, Missouri, where the corps ascended the Missouri River to its headwaters in the Rocky Mountains. After a grueling portage over the Continental Divide, they followed the Clearwater, Snake, and Columbia Rivers westward, reaching the Pacific coast in present-day Oregon in November 1805. The return trip largely retraced their outbound route, though they split into smaller parties to explore additional territory, including the Yellowstone and Marias Rivers.

This 8,000-mile odyssey mapped vast stretches of the American West, documented hundreds of plant and animal species, and established diplomatic relations with numerous Native American tribes. The expedition's detailed journals and maps became foundational resources for future westward expansion.