The Expedition traveled along the missouri river in a 55-foot boat and two smaller boats. In November 1804 Toussaint Charbonneau, a French-Canadian fur trader accompanied by his wife Sacagawea, joined the expedition as an interpreter. Then they continue on their trip and soon discovered discovers earthlodge villages of the Mandan and Hidatsas Indians. The captains decide to build Fort Mandan across the river from the main village. On December 24, 1804 they completed the Fort Mandan, and moves in for the winter.
