{{Short description|Canyon in the western United States}} {{other uses|Hells Canyon (disambiguation)}} {{Infobox valley | name = Hells Canyon | other_name = | photo = OR hells canyon.jpg | photo_width = 240 | photo_caption = Snake River flowing through the canyon <!-- MAP --> | map = USA#Idaho | map_image = | map_width = 240 | map_caption = Location in the United States##Location in Idaho | location = | country = United States | state = Idaho | state1 = Oregon, | state2 = Washington | district_type = County | district = Adams County, Idaho | district1 = <br />Idaho County, Idaho | district2 = <br />Wallowa County, Oregon, | district3 = <br>Asotin County, Washington | city = | relief = yes | label = | label_position = | coordinates = {{coord|45|22|17|N|116|38|18|W|display=inline,title}} | coordinates_ref = <ref name="gnis">{{cite web | work = Geographic Names Information System| publisher = United States Geological Survey | date = June 21, 1979 | url ={{Gnis3|383075}}| title = Hells Canyon | access-date = December 26, 2010}}</ref> <!-- Statistics --> | elevation = | elevation_m = | elevation_ft = | elevation_ref = | length = | length_mi = | length_km = | length_orientation = | length_note = | width = | width_mi = | width_km = | width_orientation = | width_note = | area = | area_mi2 = | area_km2 = | depth = | depth_ft = | depth_m = | type = | age = | border = | topo = | traversed = | river = Snake <!-- Below --> | footnotes = | embed = }} '''Hells Canyon''' is a {{convert|10|mi|km|adj=mid|-wide|spell=in}} canyon in the Western United States, along the border of eastern Oregon, western Idaho, and a small section of eastern Washington. It&nbsp;is part of the Hells Canyon National Recreation Area which is also located in part of the Wallowa-Whitman National Forest.<ref name="Hells Canyon">{{Cite book|title=Hells Canyon|publisher=World Book|year=2018}}</ref> It is North America's deepest river gorge at {{convert|7993|ft|m}},<ref>{{cite web|title=Hells Canyon National Recreation Area: Establishment of HCNRA |publisher=U.S. Forest Service |url=http://www.fs.fed.us/hellscanyon/about_us/establishment.shtml |access-date=December 26, 2010 |archive-url=https://web.archive.org/web/20101203161920/http://www.fs.fed.us/hellscanyon/about_us/establishment.shtml |archive-date=December 3, 2010 }}</ref> running deeper than the Grand Canyon in Arizona.<ref>{{Cite web|url=https://www.nationalgeographic.com/adventure/adventure-blog/2013/02/15/to-hell-and-back-out-and-back-across-north-americas-deepest-canyon/|archive-url=https://web.archive.org/web/20200407002334/https://www.nationalgeographic.com/adventure/adventure-blog/2013/02/15/to-hell-and-back-out-and-back-across-north-americas-deepest-canyon/|archive-date=April 7, 2020|title=Hells Canyon, National Geographic|website=National Geographic Society |date=15 February 2013 }}</ref>

The canyon was carved by the waters of the Snake River, which flows more than {{convert|1|mi|spell=in}} below the canyon's west rim on the Oregon side and {{convert|7400|ft|-1}} below the peaks of Idaho's Seven Devils Mountains to the east. This area includes {{cvt|214,000|acre|sqmi km2}} of wilderness;<ref name="Lanza 2007">{{Cite book|last=Lanza|first=Michael|title=Hells Canyon Wilderness|publisher=Pocket Outdoor Media|year=2007}}</ref> most of the area is inaccessible by road.<ref name = "NFS Overview">{{cite web | title = Hells Canyon National Recreation Area: Hells Canyon Overview | publisher = U.S. Forest Service | url = http://www.fs.fed.us/hellscanyon/overview/index.shtml | access-date = December 26, 2010 |archive-url=https://web.archive.org/web/20101206120003/http://www.fs.fed.us/hellscanyon/overview/index.shtml |archive-date=December 6, 2010 }}</ref>

==Geology== The geologic history of the rocks of Hells Canyon began 300 million years ago with an arc of volcanoes that emerged from the waters of the Pacific Ocean. Over millions of years, the volcanoes subsided and limestone built up on the underwater platforms. The basins between them were filled with sedimentary rock. Between 130 and 17 million years ago, the ocean plate carrying the volcanoes collided with and became part of the North American continent. A period of volcanic activity followed, and much of the area was covered with floods of basalt lava, which smoothed the topography into a high plateau.

Area rivers began carving Hells Canyon out of the plateau about 6 million years ago. Water from Lake Idaho overtopped a natural divide between it and the Salmon River around 3 million years ago, allowing the Snake River to flow through the plateau and further carve the canyon.<ref name=":0">{{Cite journal |last=Wood |first=Spencer H. |last2=Clemens |first2=Drew M. |date=July 1998 |title=Geologic and Tectonic History of the Western Snake River Plain, Idaho and Oregon |url=https://idwr.idaho.gov/wp-content/uploads/sites/2/projects/north-ada-county/199807-WOODCLEM-2002.pdf |journal=Idaho Geological Society Bulletin |volume=30 |pages=69-103}}</ref> A 2025 study concludes that the canyon is younger than previously thought, beginning only 1.6 million years ago.<ref>{{Cite news |last=Greenfieldboyce |first=Nell |date=2025-05-27 |title=Hells Canyon, the deepest gorge in the U.S., is surprisingly young |url=https://www.npr.org/2025/05/27/nx-s1-5409017/hells-canyon-deepest-gorge-young-grand-canyon |access-date=2025-05-28 |work=NPR |language=en}}</ref><ref>{{Cite journal |last=Morriss |first=Matthew C. |last2=Mitchell |first2=Nate A. |last3=Yanites |first3=Brian J. |last4=Staisch |first4=Lydia M. |last5=Korup |first5=Oliver |date=2025-05-27 |title=Cave records reveal recent origin of North America's deepest canyon |url=https://www.pnas.org/doi/10.1073/pnas.2413069122 |journal=Proceedings of the National Academy of Sciences |volume=122 |issue=21 |article-number=e2413069122 |doi=10.1073/pnas.2413069122|doi-access=free |pmc=12130896 }}</ref> Significant canyon-shaping events occurred as recently as 15,000 years ago during a massive outburst flood from Lake Bonneville in Utah.<ref>{{cite web|title=Hells Canyon National Recreation Area: Geology of Hells Canyon |publisher=U.S. Forest Service |url=http://www.fs.fed.us/hellscanyon/life_and_the_land/geology/ |access-date=December 26, 2010 |url-status=bot: unknown |archive-url=https://web.archive.org/web/20110315085105/http://www.fs.fed.us/hellscanyon/life_and_the_land/geology/ |archive-date=March 15, 2011 }}</ref> The canyon rim contains dense forests, scenic overlooks and mountain peaks. At the bottom of the canyon, the area is a dry, desert environment.<ref name="Hells Canyon" />

==History== [[File:Hells Canyon Oregon.JPG|thumb|Snake River winding<br />through Hells Canyon]]

===Inhabitants=== The earliest known residents in Hells Canyon were the Nez Percé tribe. Others tribes visiting the area were the Shoshone-Bannock, northern Paiute and Cayuse Indians. The mild winters and ample plant and wildlife attracted human habitation. Pictographs and petroglyphs on the walls of the canyon are a record of the Indian settlements.<ref name="human">{{cite web |url=http://www.fs.fed.us/hellscanyon/life_and_the_land/the_human_story/ |title=Hells Canyon National Recreation Area: The Human Story |department=Forest Service |publisher=U.S. Department of Agriculture |access-date=December 26, 2010}}</ref>

In 1806, three members of the Lewis and Clark Expedition entered the Hells Canyon region along the Salmon River. They turned back without seeing the deep parts of the canyon. It was not until 1811 that the Wilson Price Hunt expedition explored Hells Canyon while seeking a shortcut to the Columbia River. Hunger and cold forced them to turn back, as also did many explorers who were defeated by the canyon's inaccessibility. There remains no evidence in the canyon of their attempts; their expedition journals are the only documentation.<ref name="human"/> Early explorers sometimes called this area Box Canyon or Snake River Canyon.

The early miners were next to follow. In the 1860s, gold was discovered in river bars near present-day Hells Canyon National Recreation Area, and miners soon penetrated Hells Canyon; however, gold mining there was not profitable. Evidence of their endeavors remains visible along the corridor of the Snake River. Later efforts concentrated on hard-rock mining, requiring complex facilities. Evidence of these developments is visible today, especially near the mouth of the Imnaha River.<ref name="human"/>

In the 1880s there was a short-lived homesteading boom, but the weather was unsuited to farming and ranching, and most settlers soon gave up.<ref name="human"/> However, some ranchers still operate within the boundaries of the National Recreation Area.<ref name="human"/>

In May&nbsp;1887, 34&nbsp;Chinese gold miners were ambushed and killed in the area, in an event known as the Hells Canyon Massacre. No one was held accountable. Groups of white men ambushed the Chinese gold miners because of an Anti-Chinese movement that made its way to Oregon.<ref name=uw>{{cite web |url=http://www.washington.edu/uwired/outreach/cspn/Website/Classroom%20Materials/Pacific%20Northwest%20History/Lessons/Lesson%2015/15.html |title=Lesson Fifteen: Industrialization, Class, and Race: Chinese and the Anti-Chinese Movement in the Late 19th-Century Northwest |series=History of Washington State & the Pacific Northwest |department=Center for Study of the Pacific Northwest |publisher=University of Washington |access-date=12 March 2007}}</ref><ref>{{cite book |author=Nokes, R. Gregory |year=2009 |title=Massacred for Gold |place=Corvallis, Oregon |publisher=Oregon State University Press |pages=179–181}}</ref>

===Damming the Snake River=== After completion of large hydropower dams on the Columbia River in the 1930s through the 1950s, several entities sought approval from the Federal Power Commission to build dams on the Snake River, including a high dam in Hells Canyon.<ref name="Power Council"/> In 1955, the commission issued a license to the Idaho Power Company to build a three-dam complex in the canyon:

* The first of the three, Brownlee Dam, at river mile (RM)&nbsp;285 or river kilometer (RK)&nbsp;459, was finished in 1960.<ref name = "Power Council"/> * Oxbow Dam, {{convert|12|mi||round=5|spell=in}} downstream, was finished in 1972. [[File:Hells-canyon-dam-id-us.jpg|thumb|Hells Canyon Dam]] * Hells Canyon Dam, {{convert|26|mi}} below Oxbow, was completed in 1967.<ref name="Power Council">{{cite web |title=Hells Canyon Dam |publisher=Northwest Power and Conservation Council |url=http://www.nwcouncil.org/history/HellsCanyon.asp |access-date=December 26, 2010 |archive-date=November 22, 2008 |archive-url=https://web.archive.org/web/20081122103730/http://www.nwcouncil.org/history/HellsCanyon.asp }}</ref>

The three dams have a combined generating capacity of 1,167 megawatts (MW) of electricity.<ref>{{Cite web|title=Hells Canyon|url=https://www.nwcouncil.org/reports/columbia-river-history/hellscanyon|access-date=2021-05-07|website=www.nwcouncil.org|language=en}}</ref> The complex, which provides about 70&nbsp;percent of Idaho's hydroelectricity, blocks migration of salmon and other anadromous fish upstream of Hells Canyon Dam.<ref>{{cite web |title=Environmental Impact Statements (EISs): Executive Summary |publisher=Federal Energy Regulatory Commission |url=http://elibrary.ferc.gov/idmws/common/OpenNat.asp?fileID=11438420 |format=PDF |pages=xxxv & xxxviii |access-date=26 December 2010}}</ref>

Two additional dams, Mountain Sheep and Pleasant Valley, were proposed in 1955 above the mouth of the Salmon River and below the Hells Canyon Dam. The Wild and Scenic Rivers Act of 1968 held up progress, but with the energy crisis, they were revived in 1975; these projects were sponsored by consortiums Pacific Northwest Power Company and Washington Public Power Supply System (WPPSS).<ref name=pprev>{{cite news |url=https://news.google.com/newspapers?id=AqdYAAAAIBAJ&sjid=k_gDAAAAIBAJ&pg=6462%2C1756149 |newspaper=Spokane Daily Chronicle |place=(Washington) |last=Coe |first=Gordon H. |title=Power project plans revived |date=24 February 1975 |page=1}}</ref><ref name=dainpl>{{cite news |url=https://news.google.com/newspapers?id=AqdYAAAAIBAJ&sjid=k_gDAAAAIBAJ&pg=7210%2C1791780 |newspaper=Spokane Daily Chronicle |place=(Washington) |last=Coe |first=Gordon H. |type=photos, maps |title=Dams are in plans along Middle Snake |date=24 February 1975 |page=8}}</ref> At the end of that year, President Gerald Ford signed legislation to create the Hells Canyon National Recreation Area and the projects {{nowrap|were terminated.<ref name=fsnrbi>{{cite news |url=https://news.google.com/newspapers?id=67BfAAAAIBAJ&sjid=4jIMAAAAIBAJ&pg=3012%2C353013 |newspaper=Lewiston Morning Tribune |place=(Idaho) |agency=Associated Press |title=Ford signs NRA bill |date=2 January 1976 |page=16A}}</ref><ref name=fscbl>{{cite news |url=https://news.google.com/newspapers?id=fr4RAAAAIBAJ&sjid=dO0DAAAAIBAJ&pg=6732%2C274098 |newspaper=Spokesman-Review |place=(Spokane, Washington) |agency=Associated Press |title=Ford signs canyon bill |date=2 January 1976 |page=1}}</ref><ref name=llhsk>{{cite magazine |url=https://1859oregonmagazine.com/think-oregon/history/hells-canyon/ |magazine=1859: Oregon's magazine |last=Husk |first=Lee Lewis |title=Hells Canyon Fifty-Year Anniversary |date=16 July 2018 |access-date=21 March 2019}}</ref>}}

The first river runners were on the canyon rapids by 1928.<ref>{{Cite book |title=Environmental encyclopedia |date=2011 |publisher=Gale/Cengage Learning |editor=Deirdre S. Blanchfield |isbn=978-1-4144-8739-7 |edition=4th |location=Detroit |oclc=720592930}}</ref>

==Recreation== In 1975, Congress had declared {{cvt|652,000|acre|sqmi km2}} to be the recreational area for the Hells Canyon National Forest.<ref name="Lanza 2007"/> There are many recreational activities available within the canyon.<ref>Recreation: Wallowa-Whitman National Forest. Retrieved December 2, 2014, from http://www.fs.usda.gov/r06/wallowa-whitman/recreation</ref> Activities in Hells Canyon include fishing, jet boat tours, hunting, hiking, camping, and whitewater sports (mainly rafting and kayaking). Much of these activities rely on the mighty Snake River, which is the main factor in the creation of Hells Canyon. The Snake River is home to numerous fish species, an abundance of class I-IV rapids (some of the largest in the Pacific Northwest), diverse wildlife and miles of systems. There is one boat ramp that is located at the upper end of the Snake River.<ref>{{Cite web|title=Hells Canyon Creek Boat Launch|url=http://www.fs.usda.gov/r06/wallowa-whitman/recreation|access-date=7 May 2021|website=United States Department of Agriculture Forest Service}}</ref> The wildlife is made up of over 350 species and this includes big game, small game, bird, and waterfowl hunting.<ref name="Lanza 2007"/> Trophy hunting in this area consists of elk, mountain goats, mountain lions, mule deer, whitetail deer, and black bears.<ref>{{Cite web|title=Hells Canyon Outfitters {{!}} Riggins, ID 83549|url=http://www.hellscanyonoutfitters.com/|access-date=2021-05-07|website=www.hellscanyonoutfitters.com}}</ref> These key components make Hells Canyon an outdoor recreation mecca that brings in tourists from around the world. Hells Canyon offers tours year round, while most of the whitewater activities peak in summer months. To participate in these recreational activities one can utilize commercial charters or private trips.

==Access== There are three roads that lead to the Snake River between Hells Canyon Dam and the Oregon-Washington state line. There are no bridges that cross Hells Canyon.<ref name = "NFS Overview"/> From Oxbow Bridge near Copperfield, Oregon, Hells Canyon Road follows the Idaho side of the river {{convert|22|mi|km}} downstream to the Hells Canyon Dam.<ref name = "Scenic Byway">{{cite web|title = Idaho's Scenic Byways: Hells Canyon Scenic Byway|publisher = State of Idaho|url = http://www.idahobyways.gov/byways/hells-canyon.aspx|website = Idaho's Scenic Byways website|access-date = December 26, 2010|archive-url = https://web.archive.org/web/20110718215043/http://www.idahobyways.gov/byways/hells-canyon.aspx|archive-date = July 18, 2011}}</ref> The road crosses the dam and continues another mile to the Hells Canyon Visitor Center on the Oregon side.

thumb|right|alt=Deer Creek Road in Hells Canyon|Deer Creek Road looking west to Pittsburg Landing Farther north on the Idaho side, Deer Creek Road connects White Bird to the river at Pittsburg Landing.<ref name="Pittsburgh Landing">{{cite web|title = Hells Canyon National Recreation Area: Pittsburg Landing Campground|url = http://www.fs.fed.us/hellscanyon/things_to_see_and_do/idaho/recreation_sites/cg331_pittsburg.shtml|publisher = U.S. Forest Service|access-date = December 26, 2010}}</ref> Near the northern end of the canyon, Forest Road 4260 (Lower Imnaha Road), the last part of which is too rough for most cars, reaches the river at Dug Bar, {{convert|21|mi|km}} from Imnaha, Oregon.<ref name = "Sullivan">Sullivan, pp. 268–76</ref> On the canyon rims, viewpoints accessible by road include Hat Point and Buckhorn in Oregon and Heavens Gate in Idaho.<ref name = "Sullivan"/>

==See also== * Hells Canyon Wilderness (Oregon and Idaho) * List of plants endemic to Hells Canyon

==References== {{reflist}}

==Works cited== * Orr, Elizabeth L., and Orr, William N. (1999). ''Geology of Oregon'', fifth edition. Dubuque, Iowa: Kendall/Hunt Publishing Company. {{ISBN|0-7872-6608-6}}. * Sullivan, William L. (2002). ''Exploring Oregon's Wild Areas'', third edition. Seattle: The Mountaineers Press. {{ISBN|0-89886-793-2}}.

==Further reading== * Brooks, Karl Boyd (2009). ''Public Power, Private Dams: The Hells Canyon High Dam Controversy''. Seattle: University of Washington Press. {{ISBN|978-0-295-98912-9}}.

==External links== {{GeoGroup}} {{Commons category}} * [http://earthobservatory.nasa.gov/IOTD/view.php?id=37320 Nasa Earth Observatory view of the canyon]

Category:Landforms of Adams County, Idaho Category:Canyons and gorges of Oregon Category:Canyons and gorges of Idaho Category:Canyons and gorges of Washington (state) Category:Landforms of Idaho County, Idaho Category:Snake River Category:Landforms of Wallowa County, Oregon