Black Hills

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Black Hills
Needles Highway 05.jpg
The Needles, Black Hills
Highest point
Peak Black Elk Peak
Elevation 7,242 ft (2,207 m)
Coordinates 43°59′N103°45′W / 43.983°N 103.750°W / 43.983; -103.750 Coordinates: 43°59′N103°45′W / 43.983°N 103.750°W / 43.983; -103.750
Area5,000 sq mi (13,000 km2)
Usa edcp relief location map.png
Red triangle with thick white border.svg
Black Hills
Country United States
State South Dakota
Orogeny Trans-Hudson and Laramide
Age of rock Precambrian, Paleozoic, Mesozoic, Cenozoic and Tertiary
Type of rock Shale, sandstone, limestone, slate, quartzite and granite

The Black Hills (Lakota : Ȟe Sápa; Cheyenne : Moʼȯhta-voʼhonáaeva; Hidatsa : awaxaawi shiibisha [1] ) are a small and isolated mountain range rising from the Great Plains of North America in western South Dakota and extending into Wyoming, United States. [2] Black Elk Peak (formerly known as Harney Peak), which rises to 7,244 feet (2,208 m), is the range's highest summit. [3] The Black Hills encompass the Black Hills National Forest. The name "Black Hills" is a translation of the Lakota Pahá Sápa. The hills were so-called because of their dark appearance from a distance, as they were covered in trees. [4]


Native Americans have a long history in the Black Hills. After conquering the Cheyenne in 1776, the Lakota stole the territory of the Black Hills, which became central to their culture. In 1868, the U.S. government signed the Fort Laramie Treaty of 1868, establishing the Great Sioux Reservation west of the Missouri River, and exempting the Black Hills from all white settlement forever. However, when settlers discovered gold there in 1874, as a result of George Armstrong Custer's Black Hills Expedition, miners swept into the area in a gold rush. The US government took back the Black Hills and in 1889 reassigned the Lakota, against their wishes, to five smaller reservations in western South Dakota, selling off 9 million acres of their former land. Unlike most of South Dakota, the Black Hills were settled by European Americans primarily from population centers to the west and south of the region, as miners flocked there from earlier gold boom locations in Colorado and Montana.

As the economy of the Black Hills has shifted from natural resources (mining and timber) since the late 20th century, the hospitality and tourism industries have grown to take its place. Locals tend to divide the Black Hills into two areas: "The Southern Hills" and "The Northern Hills". The Southern Hills is home to Mount Rushmore, Wind Cave National Park, Jewel Cave National Monument, Black Elk Peak (the highest point in the United States east of the Rockies, formerly and still more commonly known as Harney Peak), Custer State Park (the largest state park in South Dakota), the Crazy Horse Memorial, and the Mammoth Site in Hot Springs, the world's largest mammoth research facility.

Attractions in the Northern Hills include Spearfish Canyon, historic Deadwood, and the Sturgis Motorcycle Rally, held each August. The first Rally was held on August 14, 1938 and the 75th Rally in 2015 saw more than 1 million bikers visit the Black Hills. Devils Tower National Monument, located in the Wyoming Black Hills, is an important nearby attraction and was the United States' first national monument. [5]


Satellite image with a shaded relief map of Black Hills in west South Dakota Shaded relief map of Black Hills, SD, Topographic-NatAtlas-BHills-SD.jpg
Satellite image with a shaded relief map of Black Hills in west South Dakota

Although the written history of the region begins with the Sioux domination of the land over the native Arikara tribes, researchers have carbon-dating and stratigraphic records to analyze the early history of the area. Scientists have been able to utilize carbon-dating to evaluate the age of tools found in the area, which indicate a human presence that dates as far back as 11,500 BC with the Clovis culture. Stratigraphic records indicate environmental changes in the land, such as flood and drought patterns. For example, large-scale flooding of the Black Hill basins occurs at a probability rate of 0.01, making such floods occur once in every 100 years. However, during The Medieval Climate Anomaly, or the Medieval Warm Period, flooding increased in the basins. A stratigraphic record of the area shows that during these 400 years, thirteen 100-year floods occurred in four of the region's basins, while the same four basins from the previous 800 years only experienced nine floods.

The Arikara arrived by AD 1500, followed by the Cheyenne, Crow, Kiowa and Pawnee. The Lakota (also known as Sioux) arrived from Minnesota in the 18th century and drove out the other tribes, who moved west. [6] They claimed the land, which they called Ȟe Sápa (Black Mountains). The mountains commonly became known as the Black Hills.

Gold miners in the Black Hills Custerblackhills.jpg
Gold miners in the Black Hills
Abandoned cabin near Dewey in the southern Black Hills Prairiecabin.jpg
Abandoned cabin near Dewey in the southern Black Hills

François and Louis de La Vérendrye probably traveled near the Black Hills in 1743. [7] Fur trappers and traders had some dealings with the Native Americans.

European Americans increasingly encroached on Lakota territory. After defeating the Lakota Sioux, the United States government made peace under the Fort Laramie Treaty of 1868, establishing the Great Sioux Reservation west of the Missouri River and acknowledging their control of the Teton range. In this treaty, they protected the Black Hills "forever" from a European-American settlement. Both the Sioux and Cheyenne also claimed rights to the land, saying that in their cultures, it was considered the axis mundi , or sacred center of the world.

Although rumors of gold in the Black Hills had circulated for decades (see Thoen Stone and Pierre-Jean De Smet), it was not until 1874 that Brevet Major General George Armstrong Custer of the 7th US Cavalry led an expedition there and discovered gold in French Creek. An official announcement of gold was made by the newspaper reporters accompanying the expedition. The following year, the Newton-Jenney Party conducted the first detailed survey of the Black Hills. The surveyor for the party, Dr. Valentine McGillycuddy, was the first European American to ascend to the top of Black Elk Peak. This highest point in the Black Hills is 7,242 feet above sea level.

During the 1875–1878 gold rush, thousands of miners went to the Black Hills; in 1880, the area was the most densely populated part of the Dakota Territory. Three large towns developed in the Northern Hills: Deadwood, Central City, and Lead. Around these were groups of smaller gold camps, towns, and villages. Hill City and Custer City sprang up in the Southern Hills. Railroads were quickly constructed to the previously remote area. From 1880 on, the gold mines yielded about $4,000,000 annually, and the silver mines about $3,000,000 annually.

Takeover of the Black Hills

Inyan Kara is a sacred mountain to the Lakota people Inyan-Kara.jpg
Inyan Kara is a sacred mountain to the Lakota people

The conflict over control of the region sparked the Black Hills War (1876), also known as the Great Sioux War, the last major Indian War on the Great Plains. Following the defeat of the Lakota and their Cheyenne and Arapaho allies in 1876, the United States took control of the Black Hills. The Lakota never accepted the validity of the US appropriation. They have continued to try to reclaim the property [8] and filed a suit against the federal government.

20th century land claims

On July 23, 1980, in United States v. Sioux Nation of Indians , the Supreme Court of the United States ruled that the Black Hills were illegally taken by the federal government and ordered remuneration of the initial offering price plus interest, nearly $106 million. The Lakota refused the settlement, as they wanted the Black Hills returned to them. The money remains in an interest-bearing account, which, as of 2015, amounts to over $1.2 billion, but the Lakota still refuses to take the money. They believe that accepting the settlement would allow the US government to justify taking ownership of the Black Hills.

In 2012, United Nations Special Rapporteur James Anaya conducted a 12-day tour of Native Americans' land to determine how the U.S. is carrying out the United Nations Declaration on the Rights of Indigenous Peoples, endorsed in 2010 by the Obama administration. Anaya met with tribes in seven states on reservations and in urban areas as well as with members of the Obama administration and the Senate Committee on Indian Affairs. In an appeal issued August 21, 2012, Anaya brought a sale of over 1,900 acres of land in Black Hills by the Reynolds family to the attention of the U.S. government and asked that it disclose measures taken by federal or state governments to address Sioux concerns over the sale of the land within Reynolds Prairie. These acres consist of five land tracts, including the sacred Pe' Sla site for Dakota, Lakota, and Nakota peoples; natives to the Black Hills fundraised to buy the land during the Reynolds' sale. [9] On January 15, 2013, the U.S. responded, telling Anaya that it "understands several tribes purchased the Pe' Sla sacred site around November 30, 2012" meaning the Pe' Sla is officially Sioux land. [10]


Gold-quartz placer nugget, found near Lead. About 1 cm wide. Gold-quartz placer nugget, Lead SD.jpg
Gold-quartz placer nugget, found near Lead. About 1 cm wide.

The geology of the Black Hills is complex. A Tertiary mountain-building episode is responsible for the uplift and current topography of the Black Hills region. This uplift was marked by volcanic activity in the northern Black Hills. The southern Black Hills are characterized by Precambrian granite, pegmatite, and metamorphic rocks that comprise the core of the entire Black Hills uplift. This core is rimmed by Paleozoic, Mesozoic, and Cenozoic sedimentary rocks. The stratigraphy of the Black Hills is laid out like a target, as it is an oval dome, with rings of different rock types dipping away from the center.


The granite core of the Black Hills rises 7,244 feet (2,208 m) at Black Elk Peak. Black Elk Peak hike 03.jpg
The granite core of the Black Hills rises 7,244 feet (2,208 m) at Black Elk Peak.

The 'bull's eye' of this target is called the granite core. The granite of the Black Hills was emplaced by magma generated during the Trans-Hudson orogeny and contains abundant pegmatite. The core of the Black Hills has been dated to 1.8 billion years. Other localized deposits have been dated to around 2.2 to 2.8 billion years. One of these is located in the northern hills. It is called French Creek Granite although it has been metamorphosed into gneiss. The other is called the Bear Mountain complex, and it is located in the west-central part of the hills.

The angular unconformity between the Deadwood Formation and the underlying Precambrian rocks near Rapid City. Black Hills angular deformity.jpg
The angular unconformity between the Deadwood Formation and the underlying Precambrian rocks near Rapid City.

"Making a concentric ring around the core is the metamorphic zone. The rocks in this ring are all very old, as much as 2 billion years and older. This zone is very complex, filled with many diverse rock types. The rocks were originally sedimentary until there was a collision between the North American continent and a terrane. This collision, called the Trans-Hudson Orogeny, caused the original rocks to fold and twist into a vast mountain range. Over the millions of years, these tilted rocks, which in many areas are tilted to 90 degrees or more, eroded. Today we see the evidence of this erosion in the Black Hills, where the metamorphic rocks end in an angular unconformity below the younger sedimentary layers.


The final layers of the Black Hills consist of sedimentary rocks. The oldest lie on top of the metamorphic layers at a much shallower angle. This rock called the Deadwood Formation is mostly sandstone and was the source of gold found in the Deadwood area. Above the Deadwood Formation lies the Englewood Formation and Pahasapa limestone, which is the source of the more than 200 caves found in the Black Hills, including Jewel Cave and Wind Cave. The Minnelusa Formation is next and is composed of highly variable sandstones and limestones followed by the Opeche shale and the Minnekahta limestone.


The next rock layer, the Spearfish Formation, forms a valley around the hills called the Red Valley and is often referred to as the Race Track. [11] [12] It is mostly red shale with beds of gypsum, and circles much of the Black Hills. These shale and gypsum beds, as well as the nearby limestone beds of the Minnekahta, are used in the manufacture of cement at a cement plant in Rapid City. Next is the shale and sandstone Sundance Formation, which is topped by the Morrison Formation and the Unkpapa sandstone.

The outermost feature of the dome stands out as a hogback ridge. The ridge is made out of the Lakota Formation and the Fallriver sandstone, which are collectively called the Inyan Kara Group. Above this, the layers of rocks are less distinct and are all mainly grey shale with three exceptions: the Newcastle sandstone; the Greenhorn limestone, which contains many shark teeth fossils; and the Niobrara Formation, which is composed mainly of chalk. These outer ridges are called cuestas.


Fallingrock cliff in Dark Canyon. The rock is of Paleozoic age but is capped with a Cenozoic gravel terrace. Fallingrock.jpg
Fallingrock cliff in Dark Canyon. The rock is of Paleozoic age but is capped with a Cenozoic gravel terrace.

The preceding layers were deposited horizontally. All of them can be seen in core samples and well logs from the flattest parts of the Great Plains. It took a period of uplift to bring them to their present topographical levels in the Black Hills. This uplift called the Laramide orogeny, began around the beginning of the Cenozoic and left a line of igneous rocks through the northern hills superimposed on the rocks already discussed. This line extends from Bear Butte in the east to Devils Tower in the west. Evidence of Cenozoic volcanic eruptions, if this happened, has long since been eroded.

The Black Hills also has a 'skirt' of gravel covering them in areas, which are called pediments. Formed as the waterways cut down into the uplifting hills, they represent the former locations of today's rivers. These beds are generally around 10,000 years old or younger, judging by the artifacts and fossils found. A few places, mainly in the high elevations, are older, as old as 20 million years, according to camel and rodent fossils found. Some gravels have been found but for the most part, these older beds have been eroded.[ citation needed ]


Sylvan Lake, located in Custer State Park Sylvan Lake 2016 1.jpg
Sylvan Lake, located in Custer State Park

As with the geology, the biology of the Black Hills is complex. Most of the Hills are a fire-climax ponderosa pine forest, with Black Hills spruce (Picea glauca var. densata) occurring in cool moist valleys of the Northern Hills. Oddly, this endemic variety of spruce does not occur in the moist Bear Lodge Mountains, which make up most of the Wyoming portion of the Black Hills. Large open parks (mountain meadows) with lush grassland rather than forest are scattered through the Hills (especially the western portion), and the southern edge of the Hills, due to the rainshadow of the higher elevations, are covered by a dry pine savannah, with stands of mountain mahogany and Rocky Mountain juniper.

Wildlife is both diverse and plentiful. Black Hills creeks are known for their trout, while the forests and grasslands offer good habitat for American bison, white-tailed and mule deer, pronghorn, bighorn sheep, mountain lions, and a variety of smaller animals, like prairie dogs, American martens, American red squirrels, Northern flying squirrels, yellow-bellied marmots, and fox squirrels. Biologically, the Black Hills is a meeting and mixing place, with species common to regions to the east, west, north, and south. The Hills do, however, support some endemic taxa, the most famous of which is probably white-winged junco (Junco hyemalis aikeni). Some other endemics are Cooper's Rocky Mountain snail, Black Hills subspecies of red-bellied snake, and a Black Hills subspecies of southern red-backed vole. Some birds that are only in the Black Hills and not the rest of South Dakota are pinyon jay, Canada jay, three-toed woodpecker, black-backed woodpecker, American dipper, ruffed grouse, and others.

Regions of the Black Hills

Black Hills National Forest Districts Map Black Hills National Forest Districts Map.pdf
Black Hills National Forest Districts Map

The northern Black Hills approximate Lawrence and Meade Counties and are roughly equivalent to the Northern Hills District of the Black Hills National Forest. The central Black Hills (the Mystic District of the Black Hills National Forest) are located in Pennington County west of Rapid City. The southern Black Hills are in Custer County and are administered in the national forest's Hell Canyon District. Finally, Wyoming's Black Hills follow the Bearlodge District, approximately Weston and Crook Counties.

Geologically separate from the Black Hills are the Elk Mountains, a small range forming the southwest portion of the region.

Tourism and economy

Black Hills opposite Mount Rushmore Black Hills, Mount Rushmore National Park.jpg
Black Hills opposite Mount Rushmore
Homestake Mine in 1889 Homestake works mine 1889.jpg
Homestake Mine in 1889

The region is home to Mount Rushmore National Memorial, Wind Cave National Park, Jewel Cave National Monument, Black Elk Peak, Custer State Park (the largest state park in South Dakota, and one of the largest in the US), Bear Butte State Park, Devils Tower National Monument, and the Crazy Horse Memorial. The Black Hills also hosts the Sturgis Motorcycle Rally each August. The rally was started in 1940 and the 65th Rally in 2005 saw more than 550,000 bikers visit the Black Hills. It is a key part of the regional economy. [13]

The George S. Mickelson Trail is a recently opened multi-use path through the Black Hills that follows the abandoned track of the historic railroad route from Edgemont to Deadwood. The train used to be the only way to bring supplies to the miners in the Hills. The trail is about 110 miles in length, and can be used by hikers, cross-country skiers, and cyclists. The cost is two dollars per day, or ten dollars annually.

Today, the major city in the Black Hills is Rapid City, with an incorporated population of almost 70,000 and a metropolitan population of 125,000. It serves a market area covering much of five states: North and South Dakota, Nebraska, Wyoming, and Montana. In addition to tourism and mining (including coal, specialty minerals, and the now declining gold mining), the Black Hills economy includes ranching (sheep and cattle, primarily, with bison and ratites becoming more common), timber (lumber), Ellsworth Air Force Base, and some manufacturing, including Black Hills gold jewelry, cement, electronics, cabinetry, guns and ammunition.

In many ways, the Black Hills functions as a very spread-out urban area with a population (not counting tourists) of 250,000. Other important Black Hills cities and towns include:

Panorama of the southern Black Hills Black Hills Panorama.jpg
Panorama of the southern Black Hills
Panorama of the southern Black Hills Black Hills Panorama with Trees.jpg
Panorama of the southern Black Hills

See also


  1. "Hidatsa Lessons Vocab2". Hidatsa Language Program. Archived from the original on 2013-06-06. Retrieved 2012-07-17.
  2. "Black Hills". Geographic Names Information System . United States Geological Survey.
  3. "Black Elk". NGS data sheet. U.S. National Geodetic Survey . Retrieved 2011-05-10.
  4. "Black Hills National Forest — Frequently Asked Questions". United States Forest Service.
  5. Mattison, Ray H. (1955). "The First Fifty Years". National Park Service . Retrieved January 19, 2012.
  6. "The Buffalo War". Public Broadcasting Service.
  7. "History of the Black Hills". U.S. National Park Service.
  8. Eyanopopi: The Heart of the Sioux. Irwindale, California: Centre Communications. 1988. Archived from the original on January 4, 2013. Retrieved December 3, 2012.
  9. Anaya, James (21 August 2012). "Mandate of the Special Rapporteur on the rights of indigenous peoples" (PDF). United Nations Human Rights Office of the High Commissioner. Archived from the original (PDF) on 7 October 2018.
  10. Rice, Susan (15 January 2013). "OHCHR Registry No. 01-13" (PDF). United Nations Human Rights Office of the High Commissioner.
  11. "Red Valley". Geographic Names Information System . United States Geological Survey.
  12. "Black Hills National Forest — Environment". Archived from the original on 2010-11-28. Retrieved 2010-07-27.
  13. "2017 Sturgis Rally economic impact reportedly $738 million". KEVN TV. Gray Digital Media. 12 October 2017. Retrieved 14 November 2018.

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Black Elk Peak tallest mountain in the US state of South Dakota, and the tallest mountain in the United States east of the Rocky Mountains

Black Elk Peak is the highest natural point in South Dakota, United States. It lies in the Black Elk Wilderness area, in southern Pennington County, in the Black Hills National Forest. The peak lies 3.7 mi (6.0 km) west-southwest of Mount Rushmore. At 7,242 feet (2,207 m), it has been described by the Board on Geographical Names as the highest summit in the United States east of the Rocky Mountains. Though part of the North American Cordillera, it is generally considered to be geologically separate from the Rocky Mountains. Lost Mine peak in the Chisos mountains of Texas, at an elevation of 7,535 feet, is the furthest east peak within the continental United States above 7,000 feet.

Bear Butte United States historic place

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Custer National Forest

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Black Elk Wilderness wilderness in the Black Hills National Forest, South Dakota, United States

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Great Sioux War of 1876 Battles and negotiations between the US and the Lakota Sioux and Northern Cheyenne

The Great Sioux War of 1876, also known as the Black Hills War, was a series of battles and negotiations which occurred in 1876 and 1877 between the Lakota Sioux, Northern Cheyenne, and the United States. The cause of the war was the desire of the U.S. government to obtain ownership of the Black Hills. Gold had been discovered in the Black Hills, settlers began to encroach onto Native American lands, and the Sioux and Cheyenne refused to cede ownership to the U.S. Traditionally, the United States military and historians place the Lakota at the center of the story, especially given their numbers, but some Indians believe the Cheyenne were the primary target of the U.S. campaign.

Black Hills land claim

The Black Hills land claim is an ongoing land dispute between Native Americans from the Sioux Nation and the United States government.

Deadwood Formation

The Deadwood Formation is a geologic formation of the Williston Basin and Western Canada Sedimentary Basin. It is present in parts of North and South Dakota and Montana in the United States, and in parts of Alberta, Saskatchewan, and southwestern corner of Manitoba in Canada. It is of Late Cambrian to Early Ordovician age and was named for exposures in Whitewood Creek near Deadwood, South Dakota. It is a significant aquifer in some areas, and its conglomerates yielded significant quantities of gold in the Black Hills of South Dakota.

The geology of South Dakota began to form more than 2.5 billion years ago in the Archean eon of the Precambrian. Igneous crystalline basement rock continued to emplace through the Proterozoic, interspersed with sediments and volcanic materials. Large limestone and shale deposits formed during the Paleozoic, during prevalent shallow marine conditions, followed by red beds during terrestrial conditions in the Triassic. The Western Interior Seaway flooded the region, creating vast shale, chalk and coal beds in the Cretaceous as the Laramide orogeny began to form the Rocky Mountains. The Black Hills were uplifted in the early Cenozoic, followed by long-running periods of erosion, sediment deposition and volcanic ash fall, forming the Badlands and storing marine and mammal fossils. Much of the state's landscape was reworked during several phases of glaciation in the Pleistocene. South Dakota has extensive mineral resources in the Black Hills and some oil and gas extraction in the Williston Basin. The Homestake Mine, active until 2002, was a major gold mine that reached up to 8000 feet underground and is now used for dark matter and neutrino research.