Mercer County
Sign in to savecounty in Ohio, United States
Key facts
- Country
- United States
- State
- Ohio
- Founded
- January 2, 1824
- Named after
- Hugh Mercer
- Seat
- Celina
- Largest city
- Celina
- Total
- 473 sq mi (1,230 km )
- Land
- 462 sq mi (1,200 km )
- Water
- 11 sq mi (28 km ) 2.3%
- Estimate 2025
- 42,737
- Density
- 90/sq mi (35/km )
- Time zone
- UTC−5 ( Eastern )
- Summer dst
- UTC−4 ( EDT )
- Congressional district
- 5th
- Website
- www .mercercountyohio .gov
via Wikipedia infobox
Article
Grand Lake St. Marys State Park Graftonoceras fossil nautiloid, found near Coldwater, southern Mercer County.
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.