The Winnicut River is a 9.1 mile long (14.6 km) river in the Seacoast

Seacoast Region (New Hampshire)

The Seacoast Region is the southeast area of the U.S. state of New Hampshire. The region stretches 18 miles along the Atlantic Ocean from New Hampshire's border with Salisbury, Massachusetts to the Piscataqua River and New Hampshire's border with Kittery, Maine. The shoreline is generally very...

 region of New Hampshire

New Hampshire

New Hampshire is a state in the New England region of the northeastern United States of America. The state was named after the southern English county of Hampshire. It is bordered by Massachusetts to the south, Vermont to the west, Maine and the Atlantic Ocean to the east, and the Canadian...

 in the United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

. It is the major southeastern tributary of Great Bay

Great Bay (New Hampshire)

Great Bay is a tidal estuary located in Strafford and Rockingham counties in eastern New Hampshire, United States. The bay occupies over , not including its several tidal river tributaries. Its outlet is at Hilton Point in Dover, New Hampshire, where waters from the bay flow into the Piscataqua...

, an estuary

Estuary

An estuary is a partly enclosed coastal body of water with one or more rivers or streams flowing into it, and with a free connection to the open sea....

 connected by way of the tidal Piscataqua River

Piscataqua River

The Piscataqua River, in the northeastern United States, is a long tidal estuary formed by the confluence of the Salmon Falls and Cocheco rivers...

 to the Atlantic Ocean

Atlantic Ocean

The Atlantic Ocean is the second-largest of the world's oceanic divisions. With a total area of about , it covers approximately 20% of the Earth's surface and about 26% of its water surface area...

.

The Winnicut River rises at the northern outlet of Line Swamp in the town of North Hampton, New Hampshire

North Hampton, New Hampshire

North Hampton is a town in Rockingham County, New Hampshire, United States. The population was 4,301 at the 2010 census. While the majority of the town is inland, North Hampton includes a part of New Hampshire's limited Atlantic seacoast.-History:...

, just west of Interstate 95

Interstate 95 in New Hampshire

Interstate 95, the main Interstate Highway on the east coast of the United States, cuts through the Seacoast Region of New Hampshire. The majority of it, from the Massachusetts border to the Portsmouth Circle in Portsmouth, is the 14.29-mile Blue Star Turnpike or New Hampshire Turnpike, a toll...

. The river flows north through gently rolling fields and large-lot suburban development, eventually entering the town of Greenland

Greenland, New Hampshire

Greenland is a town in Rockingham County, New Hampshire, United States. The population was 3,549 at the 2010 census. It is drained by the Winnicut River and bounded on the northwest by Great Bay.- History :...

. It crosses New Hampshire Route 33

New Hampshire Route 33

New Hampshire Route 33 is an long east–west highway in the Seacoast Region of the U.S. state of New Hampshire. It is the main road connecting Stratham with Portsmouth. The eastern terminus of NH 33 is in Portsmouth at U.S. Route 1...

 and becomes a tidal river

Tidal river

A tidal river is a river, or more typically a stretch of a river, whose flow and level is influenced by tides. An example of a tidal river is the portion of the Connecticut River flowing from Windsor Locks, Connecticut, to the Atlantic Ocean. The Brisbane River, which flows into the Pacific Ocean...

for its remaining mile to Great Bay.