The value of all farms, rural land, hunting land and other land for sale in New Jersey's Warren County recently was $83 million, representing a combined 1,385 acres of land for sale in Warren County. Warren County ranks 12th in the Garden State for the total acreage of land currently advertised for sale. There were two properties listed as sold in Warren County through the Land Network Comparable Sales Program. This represented a total value of $559,999. Hackettstown had the most land for sale. Warren County is one of the ten biggest counties in New Jersey (362 square miles). It's located in the North New Jersey region of New Jersey.