Sergeant Charles Floyd, Jr., who had been seriously ill for several days, died here of what is generally thought to be infection from a ruptured appendix. He was the expedition's only fatality. Floyd was buried on a high bluff on the east bank of the Missouri, overlooking the mouth of a river that now bears his name. The spot is marked by a 100-foot-tall sandstone obelisk completed in 1901. In 1960 the monument became the first historic landmark to be established by the U.S. Department of the Interior.