Lewis and Clark camped at the mouth of the Vermillion River near the present-day town on August 24, 1804. The previous day, they had killed their first bison; the following day, they climbed Spirit Mound. In May 1843, John James Audubon visited the Vermillion ravine to view the bird life. The town was considered for the location of South Dakota's first mental institution (now the Human Services Center) in 1873, but the hospital was eventually awarded to nearby Yankton. The original town was entirely below the bluffs on the banks of the Missouri River, and three-quarters of it washed away in the Great Flood of 1881...