A total of 5,000 acres were listed for sale in Johnson County, Kansas, recently, representing a total value of approximately $434 million in Johnson County farms, ranches, and rural real estate for sale. Johnson County ranks second in the state for the total acreage of land currently advertised for sale. Overland Park had the most land for sale. Johnson County is Kansas's 99th biggest county (479 square miles). It's located in the Wooded Hills Kansas region of Kansas.