Polk County is a county located in the central portion of the U.S. state of Florida. The county population was 602,095, as of the 2010 census. Its county seat is Bartow, and its largest city is Lakeland. Polk County comprises the Lakeland–Winter Haven Metropolitan Statistical Area. This MSA is the 87th-most populous metropolitan statistical area and the 89th-most populous primary statistical area of the United States as of July 1, 2012. The center of population of Florida is located in Polk County, near the city of Lake Wales. Polk County is home to one public university (Florida Polytechnic University), one state college (Polk State College), and four private universities. One Fortune 500 company, Publix Super Markets, has headquarters in the county. Source: Wikipedia