The Lewis and Clark National Historic Trail, a trail of approximately three thousand seven hundred miles, extending from Wood River, Illinois, to the mouth of the Columbia River in Oregon, is a linear network of historic and recreation sites that preserve and commemorate the trail and that are connected by various types of routes (land and water trails and highways) providing for retracement or approximate retracement of the historic route. The Lewis and Clark Expedition traveled from Illinois to the Pacific Ocean and back between 1804 and 1806. Tracing the courses of the Missouri and Columbia rivers, the Lewis and Clark National Historic Trail stretches through 11 states. The Trail winds over mountains, along rivers, through plains and high deserts, and extends to the Pacific coast.
In 1803, Meriwether Lewis and William Clark assembled a diverse company (The Corp of Discovery) to accomplish a task set for them by President Thomas Jefferson, who wanted to extend American influence all the way to the west coast so as to compete with the British for the fur trade, and authorized by Congress — to travel from the Mississippi Valley to the Pacific Coast, crossing outside the borders of the United States to describe an unfamiliar landscape, to find a viable commercial route across the continent, and to establish relations with unknown Native peoples. Joining the two captains and the soldiers they had recruited for the expedition was York, Clark's black slave. By winter, the Corps of Discovery had been joined by a French Canadian, Toussaint Charbonneau, who would serve as an interpreter, and a young Indian woman called Sacagawea.
The Lewis and Clark expedition lasted from 1804 to 1806. With congressional funds of $2,500, the group set out from the mouth of the Missouri River to the mouth of the Columbia River. The round trip would take them over 8,000 miles by boat, canoe, and horseback. Only one man died on the trip and two deserted. Lewis and Clark kept journals during their adventures and later published over one million words about the flora, fauna, geography, weather, and peoples of the West.