Mirey Brook is a 6.5 mile long (10.5 km) stream

Stream

A stream is a body of water with a current, confined within a bed and stream banks. Depending on its locale or certain characteristics, a stream may be referred to as a branch, brook, beck, burn, creek, "crick", gill , kill, lick, rill, river, syke, bayou, rivulet, streamage, wash, run or...

 located in southwestern 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

Tributary

A tributary or affluent is a stream or river that flows into a main stem river or a lake. A tributary does not flow directly into a sea or ocean...

 of the Ashuelot River

Ashuelot River

The Ashuelot River is a tributary of the Connecticut River, approximately long, in southwestern New Hampshire in the United States. It drains a mountainous area of , including much of the area known as the Monadnock Region...

, itself a tributary of the Connecticut River

Connecticut River

The Connecticut River is the largest and longest river in New England, and also an American Heritage River. It flows roughly south, starting from the Fourth Connecticut Lake in New Hampshire. After flowing through the remaining Connecticut Lakes and Lake Francis, it defines the border between the...

, which flows to Long Island Sound

Long Island Sound

Long Island Sound is an estuary of the Atlantic Ocean, located in the United States between Connecticut to the north and Long Island, New York to the south. The mouth of the Connecticut River at Old Saybrook, Connecticut, empties into the sound. On its western end the sound is bounded by the Bronx...

.

Mirey Brook begins in the town of Warwick, Massachusetts

Warwick, Massachusetts

Warwick is a town in Franklin County, Massachusetts, United States. The population was 750 at the 2000 census. It is part of the Springfield, Massachusetts Metropolitan Statistical Area.- History :...

, at the confluence of Mountain Brook and Kidder Brook at the foot of Mount Grace

Mount Grace

Mount Grace, , is a prominent monadnock located in north central Massachusetts in the town of Warwick, approximately two miles south of the New Hampshire border. The mountain is rugged and largely wooded, but a firetower on the summit provides expansive views of the surrounding rural countryside....

. Flowing north, the brook quickly enters the town limits of Winchester, New Hampshire

Winchester, New Hampshire

Winchester is a town in Cheshire County, New Hampshire, United States. The population was 4,341 at the 2010 census. The primary settlement in the town, where 1,733 people resided at the 2010 census, is defined by the U.S. Census Bureau as the Winchester census-designated place...

, just as the valley changes from steep and narrow to flat and wide. The brook reaches the Ashuelot River at the village of Winchester.

State Route 78

New Hampshire Route 78

New Hampshire Route 78 is a long secondary north–south state highway in Cheshire County in the southern part of the U.S. state of New Hampshire. It runs from the Massachusetts border to Winchester....

follows Mirey Brook for the brook's entire length.

A major tributary of Mirey Brook is Roaring Brook, which enters from the east near the village of Scotland, New Hampshire.