Most Distant Fountain, Montana

Half a mile south of Lemhi Pass, which goes over the Continental Divide, is the Sacajawea Memorial Area, and the Most Distant Fountain, which for years was assumed to be the source of the Missouri River, as identified by Meriwether Lewis. It is one of a few springs in the area that create small streams here on the eastern side of the Divide, that join the tributaries that flow into the Beaverhead River (which officially begins, now, where it trickles out of the base of the Clark Canyon Dam, 30 miles away). From there it meanders relentlessly over the next 50 miles until it joins the Big Hole River to form the Jefferson River, which meanders over another 50 miles until, at Three Forks, the Jefferson River joins the Madison River and the Gallatin River to form the Missouri. The Missouri, of course, merges into the Mississippi River at St. Louis, where the Corps of Discovery began its journey, up the Missouri into the Louisiana Purchase, and on which they returned, a year later, flowing back down the Atlantic side of the Divide.