A total of 1,000 acres were listed for sale in Union County recently; the combined value of all Union County farmsand rural real estate for sale was nearly $5 million. Union County ranks 89th in the Hoosier?State for the total number of acres of land currently advertised for sale. Of all locations in Union County with farms, rural land, hunting land and other land for sale, Liberty had the most land for sale. Union County is Indiana's 90th biggest county (165 square miles). It's located in the East Indiana region of Indiana.