From Switzler's Illustrated History of Missouri 1541-1877 (1879) comes this sketch of the largest Native American mound built in St. Louis near the time of its demolition in 1869. The Big Mound, as it was known, was near the intersection of Broadway and Mound Street in Old North St. Louis. It stood at least 30 feet high, was 150 feet in length, and had three terraced approaches facing the river for religious ceremonies. At one point in the 1820s, a small resort building was constructed at the top of the mound. Artifacts were found during its demolition.
Its only rival in size was the mound demolished to make way for Col. John O'Fallon's mansion in the 1850s. In 1875, ten years after O'Fallon's death, his mansion burned; it was demolished completely in 1893. The site is now O'Fallon Park.