Lee County is in Northern Illinois. Of the 102 counties in the Prairie State, 728-square-mile Lee County ranks 21st by size. There is about 1,000 acres of residential land for sale in Lee County, Illinois, based on recent Land Network data. The combined market value of farmsand rural real estate for sale here is approximately $10 million. The average price of residential land for sale in Lee County was $517,740. 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.