The Lewis and Clark expedition spent the winter on the coast of the Pacific, drenched by the frequent rainstorms.
On March 23, 1806, they began the long trek back. One group, led by Clark, retraced the expedition’s steps.
Lewis led another party down the Yellowstone River, reuniting with Clark on August 12 where the Yellowstone flows into the Missouri River. The expedition sailed down the Missouri, arriving in St. Louis to a joyful welcome on September 23, 1806.
The Lewis and Clark expedition opened up the West to further exploration and, eventually, settlement. It also solved a question that had obsessed explorers for more than 300 years.
No usable waterway cuts unbroken across North America.