Union County is in Alleghenies & Valleys Pennsylvania. Of the 67 counties in the state, Union County is 64th in terms of its size (203,358 acres). Recent Land Network data records 1,000 acres of residential land and property for sale in Pennsylvania's Union County, which is valued at a combined $8 million. The average price of residential acreage for sale in Union County was $472,741. Browse all residential land and rural property for sale in Pennsylvania 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.