Missouri Headwaters State Park occupies 535 acres at the confluence of the Jefferson, Madison, and Gallatin rivers — the point where the Missouri River officially begins. It is one of the most historically charged spots in the American West: Lewis and Clark camped here in July 1805, and the confluence was a landmark in the fur trade era that followed.
The park has several miles of walking trails along the riverbanks, with interpretive signs tracing the Corps of Discovery's journey and the geology of the valley. A low bluff above the confluence gives a good view of all three rivers meeting. The fishing is excellent — this is blue-ribbon trout water — and the park has put-in access for canoes and kayaks.
Day use only; there is a small fee. The park is 3 miles north of Three Forks off Montana Highway 286.