began dreaming of an expedition to the Pacific as early as 1792, but it wasn't until he was president that he could make his dream a reality.
The expedition from St. Louis to the Pacific Ocean and back would take two years. But there was also a long period of careful planning and study before Meriwether Lewis and William Clark led their Corps of Discovery into the unmapped wilderness.
The links below lead to chronologies of the Lewis and Clark expedition, beginning with the earliest planning.
The active planning for the Lewis and Clark Expedition began in 1803, when Meriwether Lewis was sent to Pennsylvania by President Thomas Jefferson to begin an intensive course in science instruction.
In 1804 the Lewis and Clark Expedition set out from St. Louis, traveling up the Missouri River. The year would end with them camped for the winter among the Mandan Indians in South Dakota.
1805 was the critical year for the Lewis and Clark Expedition as the Corps of Discovery overcame great difficulties and reached their ultimate goal, the Pacific coast.
In 1806 the Corps of Discovery left their winter campsite near the Pacific Ocean and set off to return to the young nation they had left behind nearly two years earlier. Harrowing experiences with Indians and grizzly bears would mark their return trip to St. Louis.