Lewis and Clark: Summer of 1804


This page details the beginning of the Lewis and Clark Expedition during the Summer of 1804


Home >> United States History >> Lewis and Clark >> Into the Wild


Lewis and Clark

Tour the EPIC Lewis and Clark Journey
Lewis and Clark Interactive
Lewis and Clark Discoveries
Corps of Discovery
Meriwether Lewis
William Clark
Thomas Jefferson
Lewis and Clark Online Activities
Lewis and Clark Printable Activities
Lewis and Clark Videos
Make Your Own Lewis and Clark Map!

Related Historical Events

Louisiana Purchase
Westward Expansion

The Epic Journey

Summer 1804 – Into the Wild
Late 1804 – Teton Sioux Territory
Winter 1804-1805 – the Mandans
April 1805 – Grizzly Country
Summer 1805 – Great Falls of the Missouri River
August 1805 – Shoshone Country
Fall 1805 – the Bitteroots
November 1805 – Columbia River
Winter 1805-1806 – Fort Clatsop
1806 – Return Trip

Lewis and Clark Bicentennial Stamp

Lewis and Clark in St. Louis

On May 14, 1804, the westward journey of Meriwether Lewis, William Clark, and 38 hunters, cooks, and frontiersmen began at St. Charles on the shores of the Missouri River. Lewis was chosen by Thomas Jefferson to explore the western lands acquired in the Louisiana Purchase. Lewis then turned to William Clark to accompany him and to recruit members who would be beneficial to the expedition. Together, the travelers would be referred to as the Corps of Discovery. Goals of the expedition included charting new animals and plants, documenting the different Native American groups of the regions, and, to find a water passage to the Pacific Ocean known as the Northwest Passage.

Lewis and Clark Summer of 1804

The Corps traveled on average 20 miles per day against the current on the Missouri River. On May 20, the expedition sailed past La Charette, the last White settlement on the Missouri River. On July 4th, the expedition celebrated the first Independence Day west of the Mississippi River. To salute the young nation’s birthday, the cannons from the keelboats were fired and a creek near present-day Atchison, Kansas was named Independence Creek.

Did You Know?

Because the Missouri River rises east of the Continental Divide, the Corps of Discovery was forced to travel against the current of the mighty Missouri River until they reached the divide in the Rocky Mountains.

At 2,341 miles in length, the Missouri River is considered the longest river in the United States.


On August 3rd, the Corps encountered Native Americans for the first time – the Yankton Sioux in the Great Plains, near present-day Omaha, Nebraska. The Yankton Sioux were presented with various medals and flags and were told of their "Great Father to the East," Thomas Jefferson. On August 20th, Kentucky frontiersman Charles Floyd died, most likely from a burst appendix brought on by appendicitis. Amazingly, Floyd’s death would prove to be the ONLY death on the entire two-year expedition. A funeral for Floyd was held on a bluff overlooking the Missouri River. The location was named Floyd’s Bluff in his honor. Although appendicitis is usually diagnosed by doctors today before the appendix bursts, in Floyd’s time, appendicitis was invariably fatal.