There was a combined almost $7 million of land and rural real estate for sale in Seneca County recently on Land.com. The total size of all Seneca County farms, ranches, hunting land and other land for sale was almost 1,000 acres. Seneca County ranks 77th out of 88 counties in the Buckeye State for the combined amount of land currently advertised for sale. Of all farms, ranches, hunting land and other land for sale in Seneca County, Tiffin had the most land for sale. Seneca County is the 22nd largest county (552 square miles) in Ohio. It's located in the Northwest Ohio region of Ohio.