The Lewis and Clark Expedition, which took place from 1804 to 1806, traversed several present-day states in the United States. Starting from St. Louis, Missouri, the route of the expedition included:
- Missouri
- Kansas
- Nebraska
- South Dakota
- North Dakota
- Montana
- Idaho
- Washington (ending at the Pacific Ocean)
Sacagawea, as a guide and translator, traveled with the expedition through these states as they made their way westward.