Mount Jefferson is a

mountain A mountain is an elevated portion of the Earth's crust, generally with steep sides that show significant exposed bedrock. Although definitions vary, a mountain may differ from a plateau in having a limited Summit (topography), summit area, and ...

located on the

Continental Divide A continental divide is a drainage divide on a continent such that the drainage basin on one side of the divide feeds into one ocean or sea, and the basin on the other side either feeds into a different ocean or sea, or else is endorheic, not ...

between Fremont County of northeastern

Idaho Idaho ( ) is a state in the Pacific Northwest region of the Western United States. To the north, it shares a small portion of the Canada–United States border with the province of British Columbia. It borders the states of Montana and Wyom ...

and

Beaverhead County Beaverhead County is the largest county by area in the U.S. state of Montana. As of the 2020 census, the population was 9,371. Its county seat is Dillon. The county was founded in 1865. Much of the perimeter of the county is the Continental Di ...

of southwestern

Montana Montana () is a state in the Mountain West division of the Western United States. It is bordered by Idaho to the west, North Dakota and South Dakota to the east, Wyoming to the south, and the Canadian provinces of Alberta, British Columbi ...

. Mount Jefferson is the highest point of the

Centennial Mountains The Centennial Mountains are the southernmost sub-range of the Bitterroot Range in the U.S. states of Idaho and Montana. The Centennial Mountains include the Western and Eastern Centennial Mountains. The range extends east from Monida Pass along ...

, whose crest runs along the Continental Divide and can be climbed using a class 2 route (scramble) from the access road to neighboring

Sawtell Peak Sawtell Peak, also spelled Sawtelle Peak is a mountain in the U.S. state of Idaho. It is located in the eastern portion of the Centennial Mountains. Sawtell Peak is located in the Caribou-Targhee National Forest roughly east of Idaho's border wi ...

. The south and west slopes of Mount Jefferson drain into Hell Roaring Creek, thence into Red Rock Creek, the Red Rock River, the Beaverhead River, the

Jefferson River The Jefferson River is a tributary of the Missouri River, approximately long, in the U.S. state of Montana. The Jefferson River and the Madison River form the official beginning of the Missouri at Missouri Headwaters State Park near Three F ...

, the Missouri River, the

Mississippi River The Mississippi River is the second-longest river and chief river of the second-largest drainage system in North America, second only to the Hudson Bay drainage system. From its traditional source of Lake Itasca in northern Minnesota, it f ...

, and into the

Gulf of Mexico The Gulf of Mexico ( es, Golfo de México) is an oceanic basin, ocean basin and a marginal sea of the Atlantic Ocean, largely surrounded by the North American continent. It is bounded on the northeast, north and northwest by the Gulf Coast of ...

Brower's Spring Brower's Spring is a spring in the Centennial Mountains of Beaverhead County, Montana that was marked by a surveyor in 1888 as the ultimate headwaters of the Missouri River and thus the fourth longest river in the world, the Mississippi-Missour ...

, the

source Source may refer to: Research * Historical document * Historical source * Source (intelligence) or sub source, typically a confidential provider of non open-source intelligence * Source (journalism), a person, publication, publishing institute o ...

of Hell Roaring Creek, on the mountain's east flank in Montana, is considered the absolute headwaters of the Missouri River. The northeast slope of Mount Jefferson drains into the South Fork of Duck Creek, thence into

Henrys Lake Henrys Lake is a small, shallow alpine lake in the western United States, in eastern Idaho. Approximately in area, at in length and in width, its surface elevation is above sea level. It is on the southwest side of the Henrys Lake Mountains ...

, the Henrys Fork of the

Snake River The Snake River is a major river of the greater Pacific Northwest region in the United States. At long, it is the largest tributary of the Columbia River, in turn, the largest North American river that empties into the Pacific Ocean. The Snake ...

, the

Columbia River The Columbia River (Upper Chinook: ' or '; Sahaptin: ''Nch’i-Wàna'' or ''Nchi wana''; Sinixt dialect'' '') is the largest river in the Pacific Northwest region of North America. The river rises in the Rocky Mountains of British Columbia, C ...

, and into the

Pacific Ocean The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the continen ...

. The mountain is named for

United States Founding Father The Founding Fathers of the United States, known simply as the Founding Fathers or Founders, were a group of late-18th-century American Revolution, American revolutionary leaders who United Colonies, united the Thirteen Colonies, oversaw the Am ...

and third president,

Thomas Jefferson Thomas Jefferson (April 13, 1743 – July 4, 1826) was an American statesman, diplomat, lawyer, architect, philosopher, and Founding Fathers of the United States, Founding Father who served as the third president of the United States from 18 ...

References

External links

* Mountains of Beaverhead County, Montana Mountains of Fremont County, Idaho Mountains of Idaho Mountains of Montana Missouri River {{FremontCountyID-geo-stub