Rockingham

Rockingham, county, extreme southeastern New Hampshire, U.S. It is bordered by Massachusetts to the south, the Atlantic Ocean to the east, and Maine and Little and Great bays to the northeast; the Piscataqua River constitutes the boundary with Maine. The county is the state’s only coastal lowland, although the terrain rises to more than 1,000 feet (305 metres) at Mount Pawtuckaway in the northwest. The principal waterways are the Exeter, Squamscott, and Lamprey rivers and...