Riley County is in Tallgrass Prairie Kansas. Of the 105 counties in the Sunflower State, 622-square-mile Riley County ranks 81st by size. There is approximately 1,000 acres of residential land for sale in Riley County, Kansas, based on recent Land Network data. The combined market value of land and rural real estate for sale here is almost $10 million. The average price of residential acreage for sale in Riley County was $1 million. Browse all residential land and rural property for sale in Kansas 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.