Meriwether Lewis and William Clark discovered 100 new animal species and 170 new plants while creating detailed maps of the new territory the United States purchased from the French during the Louisiana Purchase. The men traveled nearly 3,700 miles from the Mississippi River all the way to the Pacific Ocean on foot, horseback and boat.
The Lewis and Clark Expedition started on May 14, 1804, where the Missouri River empties into the Mississippi River. Clark was in charge of overseeing the men who accompanied them and mapping a route. This was a hard task because they had no reliable maps to use since it was new territory. Lewis collected a number of plant and animal specimens along the way and made scientific observations. Due to the rough terrain, the men only managed to travel about 12 to 14 miles on a good day.
Lewis and Clark made it back to St. Louis on September 23, 1806. Due to how long they were gone, many feared that they died on their journey. Despite the hardships the team faced while on this expedition, only one man died on the trip. Sergeant Charles Floyd died of a ruptured appendix while the group traveled down the Missouri River.