The value of all farms, hunting land and other rural land and acreage for sale in Mason County, Illinois, recently was nearly $5 million, representing a combined 278 acres of land for sale in Mason County. Mason County ranks 88th in the Inland Empire for the total acreage of land currently advertised for sale. Among cities in Mason County with farms, hunting land and other rural land and acreage for sale, Forest City featured the most land for sale. Mason County is Illinois's 47th biggest county (563 square miles). It's located in the Western Illinois region of the state.