That would be Illinois. So named for its many prairies formed by generally being in the center of one of the largest floodplains in the world. The nickname is unofficial but fairly common, and its especially used as shorthand to imply Illinois' middle American values and provincial lifestyle. Illinoisians hold up this heritage proudly, with every 3rd week in September serving as Prairie Week in the state, with its many citizens serving to better its prairies through environmental cleanup and beautification projects.