Mount Frissell, 2454 feet (748 m), located on the border of southwest Massachusetts

Massachusetts

The Commonwealth of Massachusetts is a state in the New England region of the northeastern United States of America. It is bordered by Rhode Island and Connecticut to the south, New York to the west, and Vermont and New Hampshire to the north; at its east lies the Atlantic Ocean. As of the 2010...

 and northwest Connecticut

Connecticut

Connecticut is a state in the New England region of the northeastern United States. It is bordered by Rhode Island to the east, Massachusetts to the north, and the state of New York to the west and the south .Connecticut is named for the Connecticut River, the major U.S. river that approximately...

, is a prominent peak of the Taconic Range. The peak and northern part of the mountain are located within Massachusetts. The southern slope of Mount Frissell is located within Connecticut and rises to the highest elevation within that state, 2379 feet (725 m). Bear Mountain

Bear Mountain (Connecticut)

Bear Mountain, is prominent peak of the southern Taconic Mountains. It lies within the town of Salisbury, Connecticut, in the United States, and is the highest mountain summit in the state of Connecticut. The highest point in the state, however, is located on the south slope of Mount Frissell to...

, located 1.3 miles (2.1 km) to the east, is the highest mountain summit in Connecticut.

The mountain is located within the towns of Mount Washington, Massachusetts

Mount Washington, Massachusetts

Mount Washington is a town in Berkshire County, Massachusetts, United States. It is part of the Pittsfield, Massachusetts Metropolitan Statistical Area. The population was 130 at the 2000 census, making it the smallest town in Berkshire County and, after Gosnold and Monroe, the third smallest in...

 and Salisbury, Connecticut

Salisbury, Connecticut

Salisbury is a town in Litchfield County, Connecticut, United States. The town is the northwest-most in the State of Connecticut. The MA-NY-CT Tri-State Marker is located just on the border of Salisbury...

; much of it has been conserved as part of Massachusetts' Mount Washington State Forest

Mount Washington State Forest

Mount Washington State Forest is a scenic state forest in the southern Taconic Mountains of the southwestern Berkshire region of Massachusetts. It has 30 miles of trails for hiking, as well as offering wilderness camping, fishing, horseback riding trails, and cross-country skiing...

 and Connecticut's Mount Riga Forest Preserve. The south side of Mount Frissell drains into Riga Lake and South Pond, then into Wachocostinook Brook, Salmon Creek, the Housatonic River

Housatonic River

The Housatonic River is a river, approximately long, in western Massachusetts and western Connecticut in the United States. It flows south to southeast, and drains about of southwestern New England into Long Island Sound...

, and 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...

. The northwest side drains into Ashley Hill Brook, thence Bash Bish Brook, the Roeliff Jansen Kill, the Hudson River

Hudson River

The Hudson is a river that flows from north to south through eastern New York. The highest official source is at Lake Tear of the Clouds, on the slopes of Mount Marcy in the Adirondack Mountains. The river itself officially begins in Henderson Lake in Newcomb, New York...

, and Upper New York Bay

Upper New York Bay

Upper New York Bay, or Upper Bay, is the traditional heart of the Port of New York and New Jersey, and often called New York Harbor. It is enclosed by the New York City boroughs of Manhattan, Brooklyn, and Staten Island and the Hudson County, New Jersey municipalities of Jersey City and Bayonne.It...

. The northeast side drains into Sages Ravine, thence into Schenob Brook, the Hubbard Brook, the Housatonic River, and Long Island Sound. Mount Frissell is bordered by Round Mountain

Round Mountain (Taconic Mountains)

Round Mountain, , located on the border of southwest Massachusetts and northwest Connecticut, is a prominent peak of the Taconic Range. The peak and southern slopes of the mountain are within Connecticut; the northern slope lies within Massachusetts....

 to the southeast, Mount Ashley to the north, and Brace Mountain

Brace Mountain

Brace Mountain is the peak of a ridge in the southern Taconic Mountains, near the tripoint of the U.S. states of New York, Connecticut and Massachusetts...

 to the west.

Mount Frissell is traversed by the Mount Frissell Trail which connects with the South Taconic Trail

South Taconic Trail

The South Taconic Trail is a hiking trail in the Taconic Mountains of southwest Massachusetts and adjacent New York. The trail extends from the village of Whitehouse Crossing in Millerton, New York, north along the ridgecrest of the southern Taconic Range and the border of New York and...

 to the west and the Appalachian Trail

Appalachian Trail

The Appalachian National Scenic Trail, generally known as the Appalachian Trail or simply the AT, is a marked hiking trail in the eastern United States extending between Springer Mountain in Georgia and Mount Katahdin in Maine. It is approximately long...

to the east.