Three Forks of the Missouri River

National Historic Landmark

Located along major intertribal trade and travel routes, the Missouri River headwaters was a confluence of people as well as rivers. Faded pictographs testify to long usage by Plains and Intermontane tribes, including the Shoshones, who regularly traveled here to hunt. On one such trip a Hidatsa war party kidnapped twelve-year-old Sacagawea, whom they sold to fur trader Toussaint Charbonneau. Charbonneau and Sacagawea joined Meriwether Lewis and William Clark’s Corps of Discovery at the Mandan villages in 1805, when the captains hired them as translators. Reaching Three Forks on July 27, 1805, Sacagawea told Lewis that she recognized the landscape as the site of her capture five years earlier. Although they were anxious to meet the Shoshones to trade for the horses they would need to cross the Rocky Mountains before winter, the captains understood this site as “the essential point in the geography” of the West. Naming the converging rivers after President Thomas Jefferson, Secretary of State James Madison, and Treasury Secretary Albert Gallatin, the Corps paused several days to rest, measure latitude and longitude, and explore, before choosing to follow the Jefferson to its source. Once released from duty, corps members John Colter, John Potts and George Drouillard returned to the confluence to trap beaver. Potts and Drouillard were killed and Colter barely survived violent encounters with the Blackfeet, who were determined to keep the Americans out of their territory. Retired smelterman Clark Maudlin recognized the site’s historical significance and purchased the land, which he donated to the State of Montana. Headwaters State Park opened to the public in 1951.