Near Stanton, North Dakota, at the junction of the Knife and Missouri rivers, Big Hidatsa was the largest of the three villages now preserved at Knife River Indian Villages National Historic Site. Occupied from about 1740 to 1850, it grew to about 120 round earthlodges. In the winter of 1804, Lewis and Clark found thousands of Hidatsa and Mandan people living nearby in more than 200 lodges, and after building Fort Mandan about 2 miles away, the Corps of Discovery traded here and received important local help, including assistance connected with Sacagawea. The site remains significant for both northern Plains village life and the expedition’s westward knowledge.