1 OCT. 15, 1803 CLARK COMES ABOARD “I will chearfully join you…and partake of the dangers, difficulties, and fatigues,” Clark wrote in accepting Lewis’ invitation to immortality. Clark, who was living near Louisville, spent the summer recruiting men for the expedition
2 DECEMBER 1803 WINTER CAMP After gathering additional men at Army outposts along the way, the corps encamped across from the mouth of the Missouri in what is now Illinois. Lewis gathered more supplies in St. Louis
3 MAY-NOVEMBER 1804 UP THE MISSOURI The river from St. Louis to the Mandan villages in what is now North Dakota was well traveled by trappers and traders, but the captains collected a trove of new plant and animal specimens and mapped the route carefully. Military discipline was strictly enforced, including the holding of courts-martial for desertion, drunkenness and sleeping on duty
4 WINTER 1804-05 MANDAN VILLAGES The corps spent the bitterly cold winter camped among thousands of Indians, along with French and British traders. A turning point of the expedition occurred when the captains signed on a French Canadian interpreter, who would bring along his young Shoshone wife Sacagawea
5 APRIL-AUGUST 1805 INTO THE UNKNOWN Lewis called the northern plains “beautifull in the extreme,” but knew that harder times lay ahead. On May 26, he saw the Rockies for the first time. The Indians also had told of a large waterfall on the Missouri. Lewis reached the Great Falls on June 13, only to discover five falls over a 12-mile stretch
6 AUGUST-SEPTEMBER 1805 CROSSING THE MOUNTAINS Even the backbreaking weeks spent dragging canoes 17 miles around the Great Falls did not prepare the corps for the challenge of crossing the rugged Bitterroots. In an extraordinary coincidence at the Continental Divide, the first band of Shoshone encountered by the corps turned out to be led by Sacagawea’s brother. Guided by a Shoshone, the group headed into “the most terrible mountains ever beheld.” After nearly starving among the snowy peaks for three weeks, the party made contact with the Nez Percé
7 OCTOBER-DECEMBER 1805 DOWN TO THE SEA By portaging the worst rapids with the help of Indians along the way, the explorers spotted the Pacific on Nov. 7, 1805. “O! the joy,” Clark wrote. They spent a month exploring and then selected a place to spend the winter, knowing that come spring, they would have to make the journey all over again
HIGHER LEARNING While gathering supplies for the trip, Lewis underwent a crash course with the country’s top scientists–including Thomas Jefferson
PITTSBURGH Lewis leaves Aug. 31, 1803
EARLY DISTRESS The upper Ohio River was so shallow that the keelboat kept getting stuck
CAMP RIVER DUBOIS Dec. 12, 1803, to May 13, 1804
CASUALTY On Aug. 20, 1804, Sergeant Charles Floyd died, probably of an infected appendix. He was buried on a bluff in what is now Sioux City, Iowa
FAILED AMBUSHES Fearing encroachment on its territory, Spain sent four military missions to intercept and stop Lewis and Clark. None succeeded
TENSE ENCOUNTER Lewis was under orders to foster good relations with the Teton Sioux, but through misunderstandings, the first meeting came close to violence several times
TAMED RIVER Lewis and Clark wouldn’t recognize the Missouri River today. Dams have created vast lakes over much of its course
FORT MANDAN Nov. 2, 1804, to April 6, 1805
SEPARATE WAYS On the way east in 1806, Lewis rode on horseback to explore the Marias River, where he had a deadly encounter with Blackfeet. Clark traveled down the Yellowstone River by canoe
FORT CLATSOP Dec. 7, 1805, to March 23, 1806
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