The total value of land and rural real estate for sale in Hillsborough County, New Hampshire, recently on Land.com was around $215 million. This represents almost 3,000 acres of land for sale in Hillsborough County. Hillsborough County ranks fourth in the Granite State for the total acreage of land currently advertised for sale. Of all farms and rural real estate for sale in Hillsborough County, Peterborough featured the most land for sale. Hillsborough County is one of the ten largest counties in New Hampshire (892 square miles). It's located in the South New Hampshire region of New Hampshire.