There was a combined around $14 million of farms, hunting land and other rural land and acreage for sale in New Jersey's Union County recently on Land.com. The total acreage of all Union County land and rural real estate for sale was almost 8,000 acres. Union County ranks 20th in the Garden State based on the combined acreage of land for sale of the 21 counties in the Garden State. Of all locations in Union County with farms and rural land for sale, Roselle Park had the most land for sale. Union County is New Jersey's 20th biggest county (105 square miles). It's located in the North New Jersey region of the state.