Hang Son Đoòng - wikipedia Hang Son Đoòng Hang Sơn Đoòng Sơn Đoòng Cave View approaching the second doline Location Quảng Bình Province, Vietnam Coordinates 17 ° 27 ′ 25 '' N 106 ° 17 ′ 15 '' E ﻿ / ﻿ 17.45694 ° N 106.28750 ° E ﻿ / 17.45694 ; 106.28750 Coordinates : 17 ° 27 ′ 25 '' N 106 ° 17 ′ 15 '' E ﻿ / ﻿ 17.45694 ° N 106.28750 ° E ﻿ / 17.45694 ; 106.28750 Depth Max 150m / 490ft Length Approx 9,000 m / 30,000 ft Discovery 1991 ( AD ) by Hồ - Khanh Geology Permo - Carboniferous limestone Entrances Approx 2 Hazards Underground river Cave survey 2009, British / Vietnamese Sơn Đoòng Cave ( Vietnamese : Hang Sơn Đoòng ( ( haːŋ ˧ ʂəːn ˧ ɗɔ̤ŋ ˨ ˩ ) ) ; ' cave of the mountain river ' or ' mountain cave of Đoòng ( village ) ' in Vietnamese ), is a solutional cave in Phong Nha - Kẻ Bàng National Park, Bố Trạch District, Quảng Bình Province, Vietnam. As of 2009 it has the largest known cave passage cross-section in the world, and is located near the Laos -- Vietnam border. Inside is a large, fast - flowing subterranean river. It was formed in Carboniferous / Permian limestone and is believed to be between 2 and 5 million years old. Contents 1 Discovery 2 Description 3 Tourist activities 4 Development plans 5 References 6 External links Discovery Hang Sơn Đoòng was found by a local man named Hồ Khanh in 1991. The whistling sound of wind and roar of a rushing stream in the cave heard through the entrance as well as the steep descent prevented the local people from entering the cave. Only in 2009 did the cave become internationally known after a group of cavers from the British Cave Research Association conducted a survey in Phong Nha - Kẻ Bàng from 10 to 14 April 2009. Their progress was stopped by a large, 60 - metre ( 200 ft ) high calcite wall, which was named the Great Wall of Vietnam. It was traversed in 2010 when the group reached the end of the cave passage. Description According to the Limberts, the main Sơn Đoòng cave passage is the largest known cave passage in the world by volume -- 38.4 × 10 cubic metres ( 1.36 × 10 cu ft ). It is more than 5 kilometres ( 3.1 mi ) long, 200 metres ( 660 ft ) high and 150 metres ( 490 ft ) wide. Its cross-section is believed to be twice that of the next largest passage, in Deer Cave, Malaysia. The cave runs for approximately 9 kilometres ( 5.6 mi ) and is punctuated by 2 large dolines, which are areas where the ceiling of the cave has collapsed. The dolines allow sunlight to enter sections of the cave which has resulted in the growth of trees as well as other vegetation. The cave contains some of the tallest known stalagmites in the world, which are up to 70 m tall. Behind the Great Wall of Vietnam were found cave pearls the size of baseballs, an abnormally large size. Son Doong cave doline Another view out the mouth of the cavern, showing the rainforest in its doline. Reflecting pool further inside Tourist activities In early August 2013, the first tourist group explored the cave on a guided tour at a cost of US $3,000 each. Permits are required to access the cave and are made available on a limited basis, with 800 permits available for the 2017 season, which runs from February to August. After August, heavy rains cause river levels to rise and make the cave largely inaccessible. There is currently only one expedition company with permits to enter the cave for tourism purposes. Development plans Plans are being considered to build a cable car through the cave. The proposed system would be 10.5 kilometres ( 6.5 mi ) long, and cost between $112 and $211 million. The plans are opposed by environmentalists. References ^ Jump up to : Dykes, Brett Michael ( January 3, 2011 ). `` Explorers discover spectacular caves in Vietnam ''. Yahoo !. Archived from the original on 2011 - 01 - 06. Jump up ^ `` World 's Biggest Cave Found in Vietnam ''. National Geographic. July 9, 2009. Jump up ^ Guinness World Records 2013, Page 032. ISBN 9781904994879 Jump up ^ `` Gerological Map of Vietnam, Kampuchea, and Laos ''. Retrieved 15 May 2014. Jump up ^ Edström, Martin. `` Fly Through A Colossal Cave : Son Doong in 360 ° ''. National Geographic. Retrieved 2017 - 10 - 07. Jump up ^ `` World 's largest grotto unveiled in Vietnam ''. Archived from the original on 2009 - 04 - 27. Jump up ^ `` Britons claim to find world 's largest cave ''. The Daily Telegraph. London. 30 April 2009. Jump up ^ Son Doong Cave. `` Son Doong cave, Hang Son Doong -- Map ''. Jump up ^ `` Vietnam Cave ''. National Geographic. July 2011. Retrieved 16 January 2017. ( Subscription required ( help ) ). Jump up ^ Arkell, Harriet ( 25 September 2013 ). `` Five miles long, and with its own rivers and jungle : The world 's largest cave is open for tours... you just have to trek for a day and a half and then abseil down a Vietnamese cliff to get there ''. Daily Mail. London. Retrieved 16 January 2017. Jump up ^ `` First foreign tourist group explores Son Doong Cave ''. Saigon - gpdaily. 2013 - 08 - 07. Retrieved 2013 - 08 - 08. Jump up ^ `` Son Doong Cave tours increase in popularity ''. 2015 - 01 - 15. Retrieved 2015 - 01 - 16. Jump up ^ `` Son Doong Cave Cable Car Raises Controversy ''. Vietnam.com. Retrieved 2017 - 01 - 16. External links Wikimedia Commons has media related to Son Doong Cave. `` Vietnam 's Mammoth Cavern ''. Retrieved 2010 - 12 - 21. National Geographic pictorial of Hang Sơn Đoòng `` American Film Crew 's Backstage Inside Son Doong ''. Retrieved 2015 - 05 - 18. Saigon - online - SonDoong - cave Strutner, Suzy ( September 7, 2013 ). `` World 's Largest Cave, Son Doong, Prepping For First Public Tours '' ( includes video ). The Huffington Post. Retrieved September 11, 2013. Chùm ảnh khám phá hang động đẹp và lớn nhất thế giới ( includes images ) Quảng Bình Province ( in Vietnamese ) `` In pictures : Inside Hang Son Doong, the world 's largest caves in Vietnam ''. Retrieved 2014 - 06 - 20. The Telegraph Online `` Hang Son Doong '' ( video on Vimeo ). Retrieved March 17, 2015. `` National Geographic Video March 19, 2015 ''. Fly Through a Colossal Cave : Son Doong in 360 degrees by Martin Edström Retrieved from `` https://en.wikipedia.org/w/index.php?title= Hang_Sơn_Đoòng&oldid = 807594767 '' Categories : Caves of Vietnam Landforms of Quang Binh Province 2009 in Vietnam Sơn Đoòng Cave Show caves in Vietnam Hidden categories : Pages containing links to subscription - only content Coordinates on Wikidata Wikipedia cave articles with unreferenced coordinates Articles containing Vietnamese - language text All accuracy disputes Articles with disputed statements from May 2015 Articles containing potentially dated statements from 2009 All articles containing potentially dated statements All articles with unsourced statements Articles with unsourced statements from July 2017 Articles with Vietnamese - language external links Talk Contents About Wikipedia Afrikaans Aragonés Asturianu Azərbaycanca বাংলা Беларуская Български Català Čeština Cymraeg Dansk Deutsch Eesti Ελληνικά Español Esperanto Euskara فارسی Français Frysk Galego 한국어 Հայերեն हिन्दी Hrvatski Ido Bahasa Indonesia Interlingua Íslenska Italiano Basa Jawa ქართული Қазақша Kiswahili Kreyòl ayisyen Latviešu Lietuvių Lumbaart Magyar Македонски Malti Bahasa Melayu Nederlands 日本 語 Norsk Norsk nynorsk Occitan ਪੰਜਾਬੀ Plattdüütsch Polski Português Română Русский Shqip Slovenčina Slovenščina Српски / srpski Suomi Svenska Tagalog தமிழ் Tarandíne తెలుగు ไทย Türkçe Türkmençe Українська اردو Tiếng Việt 中文 Edit links This page was last edited on 28 October 2017, at 23 : 31. 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Question: where is the largest cave in the world located
Answer: Phong Nha-Kẻ Bàng National Park, Bố Trạch District, Quảng Bình Province, Vietnam