Boundary Bald Mountain is a mountain

Mountain

Image:Himalaya_annotated.jpg|thumb|right|The Himalayan mountain range with Mount Everestrect 58 14 160 49 Chomo Lonzorect 200 28 335 52 Makalurect 378 24 566 45 Mount Everestrect 188 581 920 656 Tibetan Plateaurect 250 406 340 427 Rong River...

 located in Somerset County

Somerset County, Maine

Somerset County is a county located in the U.S. state of Maine. As of 2010, the population was 52,228. Its county seat is Skowhegan.-History:...

, 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...

, about 7.5 miles (12 km) southeast of the United States-Canada border with Quebec

Quebec

Quebec or is a province in east-central Canada. It is the only Canadian province with a predominantly French-speaking population and the only one whose sole official language is French at the provincial level....

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Boundary Bald Mtn. is flanked to the east by Ironbound Mountain, and to the west by Sandy Bay Mountain

Sandy Bay Mountain

Sandy Bay Mountain is a mountain located on the Canada-United States border, with a height of above sea level.The northeastern part of the mountain is in Somerset County, Maine, while the southwestern part is in Le Granit Regional County Municipality, Quebec....

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The north side of Boundary Bald Mountain drains via Alder Brook, Fish Brook, and Hale Brook (east to west) into the South Branch

South Branch Penobscot River

The South Branch Penobscot River is a river in Somerset County, Maine. Its source, an unnamed lake, the north end of which at is about from the Canada – United States border in Sandy Bay...

 of the Penobscot River

Penobscot River

The Penobscot River is a river in the U.S. state of Maine. Including the river's West Branch and South Branch increases the Penobscot's length to , making it the second longest river system in Maine and the longest entirely in the state. Its drainage basin contains .It arises from four branches...

, thence into the West Branch

West Branch Penobscot River

The West Branch Penobscot River is a tributary of Maine's Penobscot River. The river flows from Seboomook Lake in Seboomook, Somerset County; the lake's principal inflows are the North Branch and South Branch Penobscot River...

, the main stem of the Penobscot, and into Penobscot Bay

Penobscot Bay

Penobscot Bay originates from the mouth of Maine's Penobscot River. There are many islands in this bay, and on them, some of the country's most well-known summer colonies. The bay served as portal for the one time "lumber capital of the world," namely; the city of Bangor...

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The south side of Boundary Bald Mtn. drains via Churchill Stream, Upper Churchill Stream, and Heald Stream (east to west) into the Moose River

Moose River (Maine)

The Moose River is an river in Maine. Its source is in Beattie , on the Canada – United States border, which runs along the height of land between the watersheds of the Kennebec River in Maine and the Chaudière River in Quebec...

, thence into the Kennebec River

Kennebec River

The Kennebec River is a river that is entirely within the U.S. state of Maine. It rises in Moosehead Lake in west-central Maine. The East and West Outlets join at Indian Pond and the river then flows southward...

, and into the Gulf of Maine

Gulf of Maine

The Gulf of Maine is a large gulf of the Atlantic Ocean on the east coast of North America.It is delineated by Cape Cod at the eastern tip of Massachusetts in the southwest and Cape Sable at the southern tip of Nova Scotia in the northeast. It includes the entire coastlines of the U.S...

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