Missouri was both the beginning and the end of the Lewis and Clark Expedition. After the United States took ownership of the Louisiana Territory in St. Louis in March 1804, Meriwether Lewis, William Clark, and the Corps of Discovery left winter camp at Wood River, made a final recruiting stop in St. Charles in May 1804, and began moving up the Missouri River toward the Pacific. With 45 members at the outset, including army sergeants and privates, Clark's slave York, a French-Shawnee interpreter, and French-Canadian, French-Omaha, and French-Missouri Indian boatmen, the expedition spent 66 days crossing what is now Missouri on the westward journey and returned down the same 600 miles in only two weeks in 1806. The Missouri River dominated the early trip, as the 55-foot keelboat and two pirogues struggled against swift current, snags, shifting sandbars, driftwood, collapsing banks, heat, sand, mosquitoes, and repeated damage to masts and towropes, often forcing the crew to tow the keelboat from shore. Journal accounts recorded both the hardship and the party's determination, including the saving of the keelboat above the Grand River on June 14 through extraordinary exertion. In Missouri the expedition passed settlements, traders, caves, pictographs, forests, bluffs, prairies, creeks, and springs, while the journals captured the changing landscape from timbered eastern country to western prairie. The journey ultimately disproved a Northwest Passage, but it reached the Pacific after crossing the Rocky Mountains, met nearly 50 Indian nations, produced extensive scientific observations including detailed records of 300 previously undescribed animals and plants, and helped establish a U.S. claim to the Pacific coast. Though French and British traders had already entered and mapped parts of the Missouri River country, Lewis and Clark were the first Euro-American explorers to ascend the full Missouri River from its mouth to its source, and they returned to St. Louis in September 1806 to end one of the most important American explorations.
