Some of the cities, towns, and places in Mercer County are Black Creek, Burkettsville, Butler, Carthagena, Cassella, Celina, Center, Chattanooga, Chickasaw, Coldwater, Cranberry Prairie, Dublin, Erastus, Fort Recovery, Franklin, Gibson, Granville, Hopewell, Jefferson, Liberty, Macedon, Maria Stein, Marion, Mendon, Mercer, Montezuma, Padua, Recovery, Rockford, Sebastian, St. Henry, Union, Washington, Wayne
Mercer County is located in the U.S. state of Ohio. As of the 2020 census, the population was 42,528. Its county seat is Celina. The county was created in 1820 and later organized in 1824. It is named for Hugh Mercer, an officer in the American Revolutionary War.Mercer County comprises the Celina, Ohio Micropolitan Statistical Area