Lewis and Clark spent the winter writing a report about what they had seen so far. They sent it back to St. Louis by the keelboat because the keelboat was too deep in the water to carry them any farther up the shallow waters of the Upper Missouri. The Mandan people showed the party how to make more suitable dugout canoes – pirogues.
The expedition left the Mandan villages in April and headed upriver. From here on the expedition would be crossing territory never before seen by a European-American – including the Great Falls.
