The Gates of the Mountains Wilderness is located in the

U.S. state In the United States, a state is a constituent political entity, of which there are 50. Bound together in a political union, each state holds governmental jurisdiction over a separate and defined geographic territory where it shares its sover ...

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 ...

. Created by an act of

Congress A congress is a formal meeting of the representatives of different countries, constituent states, organizations, trade unions, political parties, or other groups. The term originated in Late Middle English to denote an encounter (meeting of a ...

in 1964, the wilderness is managed by

Helena National Forest Helena National Forest is located in west-central Montana, in the United States. Covering , the forest is broken into several separate sections. The eastern regions are dominated by the Big Belt Mountains, and are the location of the Gates of the ...

. A day use campground near the Gates of the Mountains, Meriwether Picnic site, is named in honor of

Meriwether Lewis Meriwether Lewis (August 18, 1774 – October 11, 1809) was an American explorer, soldier, politician, and public administrator, best known for his role as the leader of the Lewis and Clark Expedition, also known as the Corps of Discovery, with ...

. Gates of the Mountains Wilderness (then known as the Gates of the Mountains Wild Area) was the site of the 1949

Mann Gulch fire The Mann Gulch fire was a wildfire reported on August 5, 1949, in a gulch located along the upper Missouri River in the Gates of the Mountains Wilderness (then known as the Gates of the Mountains Wild Area), Helena National Forest, in the U.S. ...

, which claimed the lives of 13 firefighters and which was the subject of

Norman Maclean Norman Fitzroy Maclean (December 23, 1902August 2, 1990) was a Scottish-American professor at the University of Chicago who became, following his retirement, a major figure in American literature. Maclean is best known for his collection of no ...

's book ''

Young Men and Fire ''Young Men and Fire'' is a 1992 non-fiction book written by Norman Maclean. It is an account of Norman Maclean's research of the Mann Gulch fire of 1949 and the 13 men who died there. The fire occurred in Mann Gulch in the Gates of the Mountain ...

''.

U.S. Wilderness Area The National Wilderness Preservation System (NWPS) of the United States protects federally managed wilderness areas designated for preservation in their natural condition. Activity on formally designated wilderness areas is coordinated by the Na ...

s do not allow motorized or mechanized vehicles, including

bicycle A bicycle, also called a pedal cycle, bike or cycle, is a human-powered or motor-powered assisted, pedal-driven, single-track vehicle, having two wheels attached to a frame, one behind the other. A is called a cyclist, or bicyclist. Bic ...

s. Although

camping Camping is an outdoor activity involving overnight stays away from home, either without shelter or using basic shelter such as a tent, or a recreational vehicle. Typically, participants leave developed areas to spend time outdoors in more nat ...

and

fishing Fishing is the activity of trying to catch fish. Fish are often caught as wildlife from the natural environment, but may also be caught from stocked bodies of water such as ponds, canals, park wetlands and reservoirs. Fishing techniques inclu ...

are allowed with proper permit, no roads or buildings are constructed and there is also no

logging Logging is the process of cutting, processing, and moving trees to a location for transport. It may include skidding, on-site processing, and loading of trees or logs onto trucks or skeleton cars. Logging is the beginning of a supply chain ...

mining Mining is the extraction of valuable minerals or other geological materials from the Earth, usually from an ore body, lode, vein, seam, reef, or placer deposit. The exploitation of these deposits for raw material is based on the economic via ...

, in compliance with the 1964

Wilderness Act The Wilderness Act of 1964 () was written by Howard Zahniser of The Wilderness Society. It created the legal definition of wilderness in the United States, and protected 9.1 million acres (37,000 km²) of federal land. The result of a lon ...

. Wilderness areas within National Forests and

Bureau of Land Management The Bureau of Land Management (BLM) is an agency within the United States Department of the Interior responsible for administering federal lands. Headquartered in Washington DC, and with oversight over , it governs one eighth of the country's la ...

areas also allow

hunting Hunting is the human activity, human practice of seeking, pursuing, capturing, or killing wildlife or feral animals. The most common reasons for humans to hunt are to harvest food (i.e. meat) and useful animal products (fur/hide (skin), hide, ...

in season.

History

The Gates of the Mountains Wilderness were named by

Lewis and Clark Lewis may refer to: Names * Lewis (given name), including a list of people with the given name * Lewis (surname), including a list of people with the surname Music * Lewis (musician), Canadian singer * "Lewis (Mistreated)", a song by Radiohead ...

. Captain Lewis wrote on July 19, 1805, In 1918, when

Holter Dam Holter Dam is a hydroelectric straight gravity dam on the Missouri River about northeast of Helena, Montana, in the United States.''Upper Missouri River Reservoir Fisheries Management Plan, 2010-2019,'' Montana Department of Fish, Wildlife and ...

was built forming

Holter Lake Holter Dam is a hydroelectric straight gravity dam on the Missouri River about northeast of Helena, Montana, in the United States.''Upper Missouri River Reservoir Fisheries Management Plan, 2010-2019,'' Montana Department of Fish, Wildlife and ...

, the water level of the Missouri River in the Gates was raised approximately . The Gates of the Mountains area was considered multiple times for inclusion in the national park system. In 1922, Montana senator

Thomas J. Walsh Thomas James Walsh (June 12, 1859March 2, 1933) was an American lawyer and Democratic Party politician from Helena, Montana who represented Montana in the US Senate from 1913 to 1933. He was initially elected by the state legislature, and from 1 ...

suggested the idea to

National Park Service The National Park Service (NPS) is an agency of the United States federal government within the U.S. Department of the Interior that manages all national parks, most national monuments, and other natural, historical, and recreational propertie ...

(NPS) director

Stephen Mather Stephen Tyng Mather (July 4, 1867 – January 22, 1930) was an American industrialist and conservationist who was the first director of the National Park Service. As president and owner of Thorkildsen-Mather Borax Company he became a milliona ...

, writing, "you must be familiar with the locality and with the wonderfully graphic account of its marvels and beauties found in the journal of Lewis and Clark." Mather visited the site but decided that it lacked national significance and that local or state protection would be adequate to preserve it. The NPS dropped the proposal at the end of 1922, only to reconsider it in 1935 and again in the 1960s. Both times, officials reached the same conclusion: "The area is suitable for a county park or a state park." The area received its wilderness designation under the

of 1964.

Geology

The prominent gray cliffs along the Missouri River in the Gates of the Mountains are formed by

Madison Limestone The Madison Limestone is a thick sequence of mostly carbonate rocks of Mississippian age in the Rocky Mountain and Great Plains areas of the western United States. The rocks serve as an important aquifer as well as an oil reservoir in places. T ...

. At the southern entrance to the canyon the trace of the Eldorado

thrust fault A thrust fault is a break in the Earth's crust, across which older rocks are pushed above younger rocks. Thrust geometry and nomenclature Reverse faults A thrust fault is a type of reverse fault that has a dip of 45 degrees or less. If ...

juxtaposes

Proterozoic The Proterozoic () is a geological eon spanning the time interval from 2500 to 538.8million years ago. It is the most recent part of the Precambrian "supereon". It is also the longest eon of the Earth's geologic time scale, and it is subdivided ...

Belt Supergroup The Belt Supergroup is an assemblage of primarily fine-grained sedimentary rocks and mafic intrusive rocks of late Precambrian (Mesoproterozoic) age. It is more than thick, covers an area of some 200,000 km2 (77,220 sq. mi), and is considered ...

Greyson Shale over much younger Madison Limestone; this faulting was part of the

Sevier orogeny The Sevier orogeny was a mountain-building event that affected western North America from northern Canada to the north to Mexico to the south. The Sevier orogeny was the result of convergent boundary tectonic activity, and deformation occurred fr ...

. Within the canyon, caves and folded layers of Madison Limestone are found. Near the north end of the canyon, at

Mann Gulch Mann Gulch is a gulch in the Gates of the Mountains Wilderness of the upper Missouri River, north-northeast of Helena, Montana, in southeastern Lewis and Clark County. It is on the east side of the Missouri River and approximately east of Inte ...

and further north, alternating ridges and valleys reflect the alternating resistance of younger rock layers overlying the Madison Limestone. The entire canyon is an example of a superposed or antecedent stream, in which the river pre-dates the uplift of the rocks and kept pace with erosion as uplift occurred.''River Log and Road Log: Thrust Faulting near Gates of the Mountains, Lombard, Lewis & Clark Canyon'', Montana Geological Society 1994 Guidebook, James L. Cannon, Gary G. Thompson, and John R. Warne, editors Gatesofmts

References

External links

* * * * Wilderness areas of Montana Canyons and gorges of Montana Helena National Forest Protected areas of Lewis and Clark County, Montana Protected areas established in 1964 1964 establishments in Montana {{LewisandClarkCountyMT-geo-stub