Indiana is a US state, admitted to the United States as the 19th on December 11, 1816. It is located in the midwestern and Great Lakes regions of North America. Indiana is the 38th largest by area and the 15th most populous of the 50 United States. Indiana is the least extensive state in the continental US west of the Appalachian Mountains. Its capital and largest city is Indianapolis. Before it became a territory, varying cultures of indigenous peoples and historic Native Americans inhabited Indiana for thousands of years. Angel Mounds State Historic Site, one of the best preserved ancient earthwork mound sites in the United States, can be found in Southwestern Indiana near Evansville. Residents of Indiana are known as Hoosiers. The etymology of the word is disputed, but the leading theory as advanced by the Indiana Historical Bureau and the Indiana Historical Society has "Hoosier" originating from the upland South region of the U.S. as a derogatory slang term for a rough countryman, a country bumpkin.