Of 10 counties in the Granite State, Rockingham County is sixth in terms of its size (795 square miles). Rockingham County is in South New Hampshire. The total value of 1,000 acres of lakefront property recently listed for sale in New Hampshire's Rockingham County was around $2 million. Browse all waterfront property for sale in Rockingham County on the Land Network to find the marina, lakefront and other recreational property that meets your needs, from waterside land perfect as a retirement investment to existing residential waterfront land and property for hunting, fishing and other outdoor-recreation pursuits! The most common type of land for sale by combined acreage in Rockingham County is house.