There are 12 US Post Offices in Warren County serving a total of 197,519 residents equating to 16,460 residents per post office. It's estimated that approximately 315,262 packages are handled across the 12 county post offices annually. Warren County is a county located in the U.S. state of Ohio. As of the 2010 census, the population was 212,693. Its county seat is Lebanon. The county was erected May 1, 1803, from Hamilton County, and named for Dr. Joseph Warren, a hero of the Revolution who sent Paul Revere on his ride and who died at the Battle of Bunker Hill. Warren County is part of the Cincinnati-Middletown, OH-KY-IN Metropolitan Statistical Area. Along with Butler County, Warren County comprises the geographical center of the Cincinnati-Dayton Metropolitan Region, home to 3.3 million and the 14th most populous in the United States. This is the key factor to the county's rapid suburban growth."