Of 21 counties in the Garden State, Middlesex County is 13th in terms of its size (322 square miles). Middlesex County is in North New Jersey. Middlesex County, New Jersey, has almost 1,000 acres of farms for sale based on recent Land Network data. The combined market value of farms, hunting land and other rural land and acreage for sale here was approximately $1 million. Browse all Middlesex County farms for sale on the Land Network to find the farm, cattle operation, hobby farm or other farm property that's right for your future commercial or individual needs. The most common type of land for sale by combined acreage in Middlesex County is house.