Missouri Headwaters Park, Montana

This state park is located at the beginning of the Missouri River, one of the principal rivers of the USA, and an important early thoroughfare for exploration immigration westward, starting with Lewis and Clark, who camped here in 1805. Though its watershed extends further upstream to the Rocky Mountains, its official origin is here, where the Jefferson, Madison, and Gallatin Rivers meet, at Three Forks, Montana. The river flows for 2,300 miles until it reaches the Mississippi River in St. Louis, Missouri.