The Lewis & Clark Expedition

William Clark and most of the team depart their St. Louis-area camp where they had been preparing for the expedition since fall 1803. They traveled aboard a 55-foot-long keelboat and two smaller craft. (Nat Geo)

The team meets up with Merriwether Lewis and his dog Seaman on the 16th of May, and the expedition gets underway with full crew on May 20th. As they traveled, Clark spent most of his time on the keelboat, charting the course and making maps, while Lewis was often ashore, studying the rock formations, soil, animals, and plants along the way. (Nat Geo)

By the end of July the expedition arrived at present day Omaha, Nebraska. They had traveled more than 600 miles upriver form St. Louis and still they had not met a single Indian.

Sergeant Charles Floyd became the first U.S. soldier to die west of the Mississippi and the only member of the Corps to die along the journey. It is believed that a ruptured appendix was the cause of his illness and death on the twentieth of August, 1804. According to journals, Sgt. Floyd had suggested a warm bath to ease his pain; however before they could get him to the water, he had died. Floyd was buried at the top of a high round hill overlooking the river. A cedar post had his name and death date upon it.

The expedition first encountered the Yankton Sioux, a more peaceable people than their neighbors farther up the Missouri, the Teton Sioux. The Yankton were somewhat disappointed by the gifts they received—a mere five medals—and warned the Americans about the reception they would receive upriver. (Nat Geo)

Four days after the first snowfall, the expedition reached the Mandan tribe’s villages in present day North Dakota. The team began to build a fort—protection against both the bitter northern winter and attack by the Sioux. Lewis & Clark also hired Toussaint Charbonneau, a French-Canadian fur trapper as an interpreter. Charbonneau, his Shoshone wife, Sacagawea, and their baby son, Jean Baptiste, would travel with the expedition when it left Fort Mandan. (Nat Geo)

Before leaving Ft. Mandan in the early spring, the expedition sent the keelboat back down the Missouri towards St. Louis laden with specimens and maps and about a dozen team members. Six dugout canoes and the two larger pirogues were loaded with supplies and equipment for the continuing journey west. The expedition was about to take a step into territory no American had ever entered. (Nat Geo)

On June 3 the expedition came upon a fork in the river. Though the branches of the fork were of equal size, the captains believed that the southern branch was the Missouri; this would lead them to the Rockies, which they hoped to cross before the autumn snows. The rest of the men disagreed, convinced that the northern branch was the right choice. Lewis and Clark could ill afford to make the wrong choice. Scouting parties dispatched up each of the branches failed to provide answers. So Lewis decided to take three men with him up the southern branch in search of the Great Falls, which the Indians at Fort Mandan had assured him he would find. Only when he reached the falls would he know for sure he was on the Missouri. (Nat Geo)

On June 13 Lewis became the first white man to see the Great Falls of the Missouri River. But to his astonishment there were five separate falls, not one as the Indians had said—and they went on for a 12-mile (19-kilometer) stretch. Portaging around the falls was going to take much more time than he had planned. By June 16 Lewis had rejoined Clark, and six days later the portage began. It was the hardest physical task of the trip so far. More than a month would pass before the expedition was around the Great Falls and onto the next stretch of navigable water. Beyond rose the Rocky Mountains. (Nat Geo)