The Lamprey River is a 50.2-mile-long (80.8 km) river in southeastern New Hampshire, the United States. It rises in Meadow Lake in Northwood, and flows south, then generally east past Raymond, Epping, Lee, Durham and finally Newmarket. Here, it meets Great Bay, a tidal inlet of the Atlantic Ocean, to which it is connected by a tidal estuary, the Piscataqua River. The river from the Bunker Pond Dam in Epping to the confluence with the Piscassic River is part of the designated National Wild and Scenic River System.