Carroll County is a county located in the state of Ohio. As of the 2020 census, the population was 26,721. Its county seat is Carrollton, while its largest village is Minerva. It is named for Charles Carroll of Carrollton, the last surviving signer of the Declaration of Independence. Carroll County is part of the Canton-Massillon, OH Metropolitan Statistical Area, which is also included in the Cleveland-Akron-Canton, OH Combined Statistical Area. It is in the Appalachian Ohio region.

Columbiana County is a county located in the U.S. state of Ohio. As of the 2020 census, the population was 101,877. The county seat is Lisbon and its largest city is Salem. Created in 1803, the county name is derived from that of 15th-century Italian explorer Christopher Columbus.