Land for sale in Fairfield County recently totaled nearly $105 million and almost 2,000 acres. Fairfield County ranks 20th in Ohio for the total acreage of land currently advertised for sale. Of all locations in Fairfield County with land for sale, Lancaster had the most land for sale. Fairfield County is Ohio's 29th biggest county (508 square miles). It's located in the Central Ohio region of Ohio.