Of 14 counties in the Bay State, Middlesex County ranks fifth in terms of size (846 square miles). Middlesex County is in Northeast Massachusetts. Massachusetts's Middlesex County has 1,000 acres of commercial land and property for sale based on recent Land Network data. The combined market value of farms, rural land, hunting land and other land for sale here was around $6 million. Browse all Middlesex County commercial acreage for sale on the Land Network to find your next commercial property or land investment. The most common type of land for sale by combined acreage in Middlesex County is residential property.