One important legacy of the Lewis and Clark Expedition was its redefinition of the geographic understanding of the American west. William Clark, the primary cartographer for the expedition, drafted incredibly accurate maps that showed unknown geographic features such as the multiple ranges of the Rocky Mountains, the Great Falls of the Missouri, and the Three Forks of the Missouri. Although not formally trained as a cartographer, Clark's innate abilities combined with his utilization of exhisting maps and informants, helped produce excellent maps. Clark's map of the expedition's track was finally published in 1814, and served as a standard for other explorers and cartographers up until the 1840s.