Monroe County is in Southwest Illinois. Of the 102 counties in the Prairie State, Monroe County ranks 75th in terms of size (398 square miles). The total value of about 1,000 acres of residential land and property recently listed for sale in Monroe County, Illinois, was around $14 million. The average price of residential acreage for sale in Monroe County was $436,275. Browse all residential land and rural property for sale in Illinois to find residential land and properties that suit your lifestyle needs, from existing residential homes and estates to land ready for future residential-property development.