Editing Subterranean river

{{short description|River that runs wholly or partly beneath the ground surface}}
[[File:Burger OtokKriznaJama.jpg|thumb|upright=1.3|A subterranean river in the [[Cross Cave]] system of [[Slovenia]]. (Scale shown by people in photograph.)]]
A '''subterranean river''' (also known as an '''underground river''') is a [[river]] or [[watercourse]] that runs wholly or partly beneath the [[land|ground]], one where the riverbed does not represent the surface of the Earth.<ref>{{Cite web |last=Sosa |first=Jeff |date=2024-06-21 |title=What is a underground river called? |url=https://www.ncesc.com/geographic-faq/what-is-a-underground-river-called/ |access-date=2025-02-12 |website=Geographic FAQ Hub: Answers to Your Global Questions |language=en-US}}</ref> It is distinct from an [[aquifer]], which may flow like a river but is contained within a [[Permeable rock|permeable]] layer of rock or other unconsolidated materials. A river flowing below ground level in an open [[gorge]] is not classed as subterranean.<ref>[https://archive.org/details/cu31924013977560 William Herbert Hobbs, ''Earth Features and Their Meaning: An Introduction to Geology for the Student and the General Reader'', Macmillan, 1912, pages 182 and 189.]</ref>

Some natural rivers may be entirely subterranean, collecting in and flowing through [[cave]] systems. In [[karst topography]], rivers that originate above ground can disappear into [[sinkhole]]s, continuing underground until they reappear on the surface downstream, possibly having merged with other subterranean rivers. The longest subterranean river in the world is the [[Sistema Sac Actun]] cave system in Mexico.<ref>"Underwater cave is the world’s biggest", Mexico Daily News, January 15, 2018, https://mexiconewsdaily.com/news/underwater-cave-is-worlds-biggest/ {{Webarchive|url=https://web.archive.org/web/20181106151230/https://mexiconewsdaily.com/news/underwater-cave-is-worlds-biggest/ |date=2018-11-06 }}</ref>

Subterranean rivers can also be the result of covering over a river or diverting its flow into [[culvert]]s, usually as part of [[urban development]].<ref name="heggen">Richard J. Heggen: ''[http://www.unm.edu/~rheggen/UndergroundRivers.html Underground Rivers from the River Styx to the Rio San Buenaventura with Occasional Diversions] {{Webarchive|url=https://web.archive.org/web/20160721162218/http://www.unm.edu/~rheggen/UndergroundRivers.html |date=2016-07-21 }}'', University of New Mexico.</ref> Reversing this process is known as [[daylighting (streams)|"daylighting"]] a watercourse and is a major form of visible river restoration. Successful examples include the [[Cheonggyecheon]] in the centre of [[Seoul]].<ref>{{cite news |first= Andrew C. |last= Revkin |title= Rolling Back Pavement to Expose Watery Havens |url= https://www.nytimes.com/2009/07/17/world/asia/17daylight.html?_r=1 |work= [[New York Times]] |date=16 July 2009|access-date=16 March 2010}}</ref><ref>{{cite news 
 | first =Donald
 | last =Kirk
 | url =http://www.csmonitor.com/2005/1013/p07s01-woap.html
 | title =Seoul peels back concrete to let a river run freely once again
 | work =World>Asia Pacific
 | publisher =The Christian Science Monitor 
 | date =2005-10-13
 | access-date =2006-08-21
}}</ref>

Some fish (colloquially known as [[cavefish]]) and other [[troglobite]] organisms are adapted to life in subterranean rivers and lakes.<ref>William B. White and David C. Culver (eds), ''Encyclopedia of Caves'', 2nd ed, Academic Press, 2012, {{ISBN|0123838339}}, [https://books.google.com/books?id=aH3ymyEURHoC&pg=PA468 p. 468.]</ref>

Examples of subterranean rivers [[#Mythology_and_literature|also occur]] in mythology and literature.

==Natural examples==
[[File:Buna source.jpg|thumb|200px|right|The cave of [[Vrelo Bune|source of the Buna]] can be entered by boat and dived through a cave system serving as an effluence of the [[Zalomka river|Zalomka]].]]
[[File:Caves entranceexit.jpg|thumb|200px|right|The [[Puerto Princesa Subterranean River National Park|Puerto Princesa]] cave can be entered by boat.]]
[[File:La chute d'entrée de la Gorge du Diable.jpg|200x200px|thumb|right|Devil's Throat Cave subterranean river from above]]
There are many natural examples of subterranean rivers. Among them:
*In [[Bosnia and Herzegovina]]: [[Unac (river)|Unac]]; Mušnica-[[Trebišnjica]]-[[Krupa (Neretva)|Krupa]]/[[Ombla]] ''(Ombla springs out of huge cave near [[Dubrovnik]], [[Croatia]] and after just ca. 30 meters empties into [[Adriatic Sea]]'s [[ria]] called [[Rijeka Dubrovačka]])''; [[Zalomka river|Zalomka]]-[[Buna (Neretva)|Buna]]/[[Bunica (river)|Bunica]]/[[Bregava]]; [[Vrljika River|Vrljika]]-[[Trebižat (river)|Trebižat]]; [[Lištica (river)|Lištica]]-Jasenica; [[Šuica (river)|Šuica]]-Ričina<ref name="Dinarides-devonkarst.org.uk">{{cite web |title=Devon Karst: Karst of the Dinaric Alps - the Dinarides in Bosnia and Herzegovina |url=http://www.devonkarst.org.uk/Karstography%20of%20DINARIC%20KARST%20in%20BiH.html |website=devonkarst.org.uk |access-date=5 July 2018 |archive-date=16 August 2020 |archive-url=https://web.archive.org/web/20200816113149/http://www.devonkarst.org.uk/Karstography%2520of%2520DINARIC%2520KARST%2520in%2520BiH.html |url-status=dead }}</ref><ref name="Ponor-Dobrelji-devonkarst.org.uk">{{cite web |title=Devon Karst: Gatačko Polje - GP-Ponor Dobrelji |url=http://www.devonkarst.org.uk/Gatacko%20Polje/GP-Ponor%20-%20Dobrelji.html |website=devonkarst.org.uk |access-date=5 July 2018}}</ref>
*In [[Bulgaria]]:
**[[Banderishki Lakes|Banderishka reka]], subterranean section below [[Kutelo]] Peak, [[Pirin|Pirin Mountain]]
**[[Struma River]] subterranean currents in [[Duhlata|Duhlata cave]], [[Vitosha]] Mountain
**Negovanka River subterranean currents in [[Emen, Bulgaria|Emen cave]], [[Veliko Tarnovo]] Province
**[[Trigrad Gorge|Trigradska reka]], subterranean section where [[Devil's Throat Cave]] and [[Trigrad Gorge]], [[Rhodope Mountains]]
*The [[Camuy River]] located in the northwestern region of [[Puerto Rico]] is one of the<ref>{{cite web|url=http://places.eyetour.com/whatToSee/camuy/56/parque-de-las-cavernas-del-rio-camuy|title=Parque de las Cavernas del Río Camuy - Video Guide - Camuy, Puerto Rico - EyeTour.com|website=places.eyetour.com}}</ref> largest underground river systems in the world.
* The [[Cross Cave]] system in [[Loška Dolina]], [[Slovenia]] includes 22 [[subterranean lake]]s
* The [[Lost River (Cacapon River)|Lost River]] in the [[Appalachian Mountains]] of [[West Virginia]] disappears underground and reappears as the [[Cacapon River]]
* The [[Mojave River]] in southern [[California]] flows underground in most places
* The [[Phong Nha-Kẻ Bàng National Park]] in [[Vietnam]] has an underground river flowing through its cave system
* The [[Puerto Princesa Subterranean River National Park|Puerto Princesa Subterranean River]] on the island of [[Palawan]], [[Philippines]] flows underground before emerging into the [[South China Sea]]<ref>{{cite web|url=http://www.officialgazette.gov.ph/2012/09/05/administrative-order-no-29-s-2012/|title=Administrative Order No. 29, s. 2012 - GOVPH|website=officialgazette.gov.ph|date=5 September 2012 }}</ref>
* The [[Punkva]] in [[Moravian Karst]], [[Moravia]], [[Czech Republic]]  underground river flowing through cave system - [[Punkva Caves]] and [[Macocha Gorge|Macocha gorge]].
* The [[Santa Fe River (Florida)|Santa Fe River]] in northern [[Florida]] drops into a large [[sinkhole]] in [[O'Leno State Park]] and reappears in the adjacent [[River Rise Preserve State Park]], {{convert|3|mi}} downstream.
* The [[Reka (river)|Reka]] in Slovenia, which disappears in the [[Škocjan Caves]], re-emerges as part of the [[Timavo]] in Italy.<ref>{{Cite journal |last=ALEXANDER |first=PAUL B. |date=1970 |title=The Reka-Timavo River System of the Yugoslavian and Italian Karst |url=https://www.jstor.org/stable/24041059 |journal=Yearbook of the Association of Pacific Coast Geographers |volume=32 |pages=157–165 |jstor=24041059 |issn=0066-9628}}</ref>

==Artificial examples==
[[File:Effra vauxhall 2.jpg|thumb|The [[River Effra|Effra]] is one of the [[subterranean rivers of London]]. It empties into the [[River Thames|Thames]] by [[Vauxhall Bridge]], from which this photograph was taken.]]
In many cities there are natural streams which have been partially or entirely built over. Such man-made examples of subterranean [[urban stream]]s are too numerous to list, but notable examples include:
* The [[Bièvre (river)|Bièvre]] underneath [[Paris]], France
* The [[Boyanska reka]] ([[Boyana]] river), partially underneath [[Sofia]], [[Bulgaria]]
* [[Castle Frank Brook]], [[Garrison Creek (Ontario)|Garrison Creek]], [[Russell Creek (Ontario)|Russell Creek]], and [[Taddle Creek]], and [[Toronto waterway system|other subterranean urban streams]] in [[Toronto]]
* The [[River Farset]], which Belfast is named after, which runs in tunnels underneath the city.
* The [[River Fleet|Fleet]] and other [[subterranean rivers of London]]
* The [[River Frome, Bristol|Frome]] underneath [[Bristol]]
* The [[Hobart Rivulet]] in [[Tasmania]]
* [[Mill Creek (Philadelphia)|Mill Creek]] in [[Philadelphia]]
* The [[Neglinnaya River]], which runs through a series of tunnels underneath the central part of [[Moscow]]
* The [[Park River (Connecticut)|Park River]] underneath [[Hartford, Connecticut|Hartford]]
* The [[Spirit Lake (Washington)|Spirit Lake]] Outlet Tunnel underneath Harry's Ridge in [[Skamania County]], [[Washington (state)|Washington]], [[United States]]
* The [[River Team]] underneath the [[Team Valley]] Trading Estate, [[Gateshead]], [[United Kingdom]]
* The [[Tank Stream]] underneath [[Sydney]], Australia
* The [[Zenne]] underneath [[Brussels]], following the [[covering of the Zenne]] between 1865 and 1871

* [[Subterranean rivers of London]]
* [[Subterranean rivers in Hong Kong]]
==Ecology==
Some fish (popularly known as [[cavefish]]) and other [[troglobite]] organisms are adapted to life in subterranean rivers and lakes.

==Mythology and literature==
{{globalize section|Europe|date=January 2024}}
[[File:Gustave Doré - Dante Alighieri - Inferno - Plate 9 (Canto III - Charon).jpg|thumb|upright|right|In [[Dante Alighieri|Dante]]'s ''[[Inferno (Dante)|Inferno]]'', [[Charon (mythology)|Charon]] ferries souls across the subterranean river [[Acheron]].]] 
Greek mythology included the [[Styx]], [[Phlegethon]], [[Acheron]], [[Cocytus]], and [[Lethe]] as rivers within the [[Greek underworld|Underworld]]. [[Dante Alighieri]], in his ''[[Inferno (Dante)|Inferno]]'', included the [[Acheron]], [[Phlegethon]], and [[Styx]] as rivers within his subterranean [[Hell]]. Similar references were made in [[John Milton]]'s ''[[Paradise Lost]]''. The river Alph, running "Through caverns measureless to man / Down to a sunless sea" is central to the poem [[Kubla Khan]], by [[Samuel Taylor Coleridge]].

The characters in [[Jules Verne]]'s ''[[Journey to the Center of the Earth]]'' encounter a subterranean river:

<blockquote>
"Hans was not mistaken," he said. "What you hear is the rushing of a torrent."

"A torrent?" I exclaimed.

"There can be no doubt; a subterranean river is flowing around us."<ref>[[Jules Verne]], ''[[Journey to the Center of the Earth]]'', translated by Frederick Amadeus Malleson, 1877, [https://www.gutenberg.org/ebooks/3748 at Project Gutenberg].</ref>
</blockquote>

Several other novels also feature subterranean rivers.<ref name="heggen"/> The [[subterranean rivers of London]] feature in the novel ''Drowning Man'' by [[Michael Robotham]] as well as in the novel ''[[Thrones, Dominations]]'' by [[Dorothy L. Sayers]] and [[Jill Paton Walsh]] in which a character remarks:

<blockquote>
"You can bury them deep under, sir; you can bind them in tunnels, but in the end where a river has been, a river will always be."<ref>[[Dorothy L. Sayers]] and [[Jill Paton Walsh]], ''[[Thrones, Dominations]]'', Hodder and Stoughton, 1998, p. 313.</ref>
</blockquote>

==See also==
*{{annotated link|Abîme}}
*{{annotated link|Karst}}
*{{annotated link|Losing stream}}
*{{annotated link|Speleology}}
*{{annotated link|Subterranean waterfall}}
*{{annotated link|Underground lake}}

== References ==
{{Commons category|Underground rivers}}
{{reflist}}

{{Caves}}
{{Rivers, streams and springs}}
{{Subterranea}}

[[Category:Subterranean rivers| ]]
[[Category:Dinaric karst formations]]
[[Category:Hydrology and urban planning]]
[[Category:Fluvial landforms]]
[[Category:Sinking rivers|*]]
[[Category:Hydrology]]