A Metro Area is generally a core area containing a large population nucleus, together with adjacent communities having a high degree of economic and social integration with that core. According to the U.S. Census, Illinois has seven statistical intrastate metro areas (Bloomington-Normal, Champaign-Urbana, Chicago, Decatur, Peoria-Pekin, Rockford, and Springfield) and two statistical interstate metro areas (much of the St. Louis, Missouri, metro area is in Illinois; and the Quad Cities consists of a core nucleus of Moline and Rock Island, Illinois, and Davenport and Bettendorf, Iowa).