A total of almost 200,000 acres were listed for sale in Suffolk County recently, representing a combined approximately $6 million in Suffolk County land and rural real estate for sale. Based on the combined acreage of land and rural property for sale here, Suffolk County has the most land for sale of all counties in the Bay State. Boston featured the most land for sale. Suffolk County is Massachusetts's 14th biggest county (120 square miles). It's located in the Northeast Massachusetts region of Massachusetts.