they landed at the mouth of the columbia river
Missouri River
No, Lewis and Clark followed the Missouri River for most of their journey, not the Mississippi River. They explored the western portion of the United States in search of a water route to the Pacific Ocean.
That the columbia river.
pacific ocean or columbia river
They split at the mouth of the Medicine River
They were trying to get across the river
Missouri
The Journey--Lewis and Clark Expedition: A National Register of Historic Places Travel Itinerary. In December 1803, William Clark established "Camp River Dubois" on the Wood River at the confluence of the Mississippi and Missouri rivers, north of St. Louis, Missouri, and across the river in Illinois.
Lewis and Clark finally arrived at the Pacific Ocean at Astoria, on the mouth of the Columbia River,
Lewis and Clark landed at the mouth of the Columbia River, Astoria, Oregon on November 7 1805.
The Columbia or Missouri River. I think :)