Great Falls Portage

The Great Falls Portage is the route taken by the Lewis and Clark Expedition in 1805 to portage around the Great Falls of the Missouri River during the outbound portion of the expedition. The portage took 31 days. Two portions of the route, which have largely escaped development, are part of a National Historic Landmark District, designated in 1966 to commemorate this achievement. In May 2008 the National Trust for Historic Preservation listed the site on their list of America's Most Endangered Places.