Lewis and Clark return

On September 23, 1806, Lewis and Clark returned to St Louis from the Pacific Northwest. From the article:

"Lewis and Clark return to St. Louis
Amid much public excitement, American explorers Meriwether Lewis and William Clark return to St. Louis, Missouri, from the first recorded overland journey from the Mississippi River to the Pacific coast and back. The Lewis and Clark Expedition had set off more than two years before to explore the territory of the Louisiana Purchase.

Even before the U.S. government concluded purchase negotiations with France, President Thomas Jefferson commissioned his private secretary Meriwether Lewis and William Clark, an army captain, to lead an expedition into what is now the U.S. Northwest. On May 14, the “Corps of Discovery,” featuring 28 men and one woman—a Native American named Sacagawea—left St. Louis for the American interior.

The expedition traveled up the Missouri River in six canoes and two longboats and wintered in Dakota before crossing into Montana, where they first saw the Rocky Mountains. On the other side of the Continental Divide, they were met by Sacagawea’s tribe, the Shoshone Indians, who sold them horses for their journey down through the Bitterroot Mountains. After passing through the dangerous rapids of the Clearwater and Snake rivers in canoes, the explorers reached the calm of the Columbia River, which led them to the sea. On November 8, 1805, the expedition arrived at the Pacific Ocean, the first European explorers to do so by an overland route from the east. After pausing there for winter, the explorers began their long journey back to St. Louis.

On September 23, 1806, after two and a half years, the expedition returned to the city, bringing back a wealth of information about the largely unexplored region, as well as valuable U.S. claims to Oregon Territory."