The East Branch of the Dead Diamond River is a 12.7 miles (20.4 km) long (20.4 km) river

River

A river is a natural watercourse, usually freshwater, flowing towards an ocean, a lake, a sea, or another river. In a few cases, a river simply flows into the ground or dries up completely before reaching another body of water. Small rivers may also be called by several other names, including...

 in northern 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 a tributary of the Dead Diamond River

Dead Diamond River

The Dead Diamond River is an 18.7 mile long river in northern New Hampshire in the United States. Its water enters the Atlantic Ocean on the coast of Maine by passing through the Magalloway, Androscoggin, and Kennebec rivers....

, located in the Androscoggin River

Androscoggin River

The Androscoggin River is a river in the U.S. states of Maine and New Hampshire, in northern New England. It is long and joins the Kennebec River at Merrymeeting Bay in Maine before its water empties into the Gulf of Maine on the Atlantic Ocean. Its drainage basin is in area...

 watershed

Drainage basin

A drainage basin is an extent or an area of land where surface water from rain and melting snow or ice converges to a single point, usually the exit of the basin, where the waters join another waterbody, such as a river, lake, reservoir, estuary, wetland, sea, or ocean...

 of Maine

Maine

Maine is a state in the New England region of the northeastern United States, bordered by the Atlantic Ocean to the east and south, New Hampshire to the west, and the Canadian provinces of Quebec to the northwest and New Brunswick to the northeast. Maine is both the northernmost and easternmost...

 and New Hampshire.

The East Branch of the Dead Diamond River rises in the town of Pittsburg, New Hampshire

Pittsburg, New Hampshire

Pittsburg is a town in Coos County, New Hampshire, United States. The population was 869 at the 2010 census. It is the northernmost town in New Hampshire and the largest town by area in the state - and in New England as well - more than twice the size of the next largest town, Lincoln. U.S...

 between 3627 feet (1,105.5 m) Stub Hill and 3230 feet (984.5 m) Diamond Ridge. Nearly the entire length of the river is in Pittsburg, with a small portion at its southern end in the Atkinson and Gilmanton Academy Grant

Atkinson and Gilmanton Academy Grant, New Hampshire

Atkinson and Gilmanton Academy Grant is a township in Coos County, New Hampshire, United States. It was granted by the state legislature to Gilmanton Academy and Atkinson Academy in equal shares in 1809 and contained about . It was later expanded by annexation of previously ungranted land to the...

. A highlight along the river are the 40 feet (12.2 m) high Garfield Falls.