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Meriwether Lewis departed Pittsburgh on August 31, 1803, in a 55-foot keelboat,
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August 31

Lewis and Clark Depart: Mapping the American West

Meriwether Lewis departed Pittsburgh on August 31, 1803, in a 55-foot keelboat, beginning the expedition that would map the American West and fulfill Thomas Jefferson's vision of a transcontinental nation. William Clark joined him at Clarksville, Indiana, and together they led the Corps of Discovery up the Missouri River, across the Rocky Mountains, and down the Columbia River to the Pacific Ocean, returning in September 1806. The expedition covered roughly 8,000 miles, documented 178 plants and 122 animals previously unknown to Western science, and established diplomatic contact with dozens of Native American nations. Sacagawea, a teenage Shoshone woman, served as interpreter and guide. Lewis and Clark's journals remain the most detailed record of pre-settlement western North America.

August 31, 1803

223 years ago

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