A total of around 1,000 acres were listed for sale in Pennsylvania's Northumberland County recently, representing a total value of around $21 million in Northumberland County farms, rural land, hunting land and other land for sale. Northumberland County ranks 47th out of 67 counties in the state for the total number of acres of land currently advertised for sale. Of all farms, rural land, hunting land and other land for sale in Northumberland County, Northumberland featured the most land for sale. Northumberland County is Pennsylvania's 48th largest county (477 square miles). It's located in the Alleghenies & Valleys Pennsylvania region of the state.