The following is a list of the world's 10 longest caves per length of documented passageways. Many passageways are still being discovered, this list is based on the latest verifiable data.

Geographical distribution

Caves are found around the world. The largest form in areas of karst

KARST

Kilometer-square Area Radio Synthesis Telescope is a Chinese telescope project to which FAST is a forerunner. KARST is a set of large spherical reflectors on karst landforms, which are bowlshaped limestone sinkholes named after the Kras region in Slovenia and Northern Italy. It will consist of...

 soils whose rocks erode easily and create caves. Preferable conditions for cave formation are adequate precipitation, enough plants and animals to produce ample carbon dioxide, and a landscape of gentle hills which drains slowly. The highest concentration of long caves in the world are found in the Pennyrile

Pennyroyal Plateau

The Pennyroyal Plateau, or, as it is more commonly called in Kentucky, the Pennyrile, is a large area of the state that features rolling hills, caves, and karst topography in general. It is also called the "Mississippi Plateau"....

 of Southern Kentucky

Kentucky

The Commonwealth of Kentucky is a state located in the East Central United States of America. As classified by the United States Census Bureau, Kentucky is a Southern state, more specifically in the East South Central region. Kentucky is one of four U.S. states constituted as a commonwealth...

, USA, and in the Black Hills

Black Hills

The Black Hills are a small, isolated mountain range rising from the Great Plains of North America in western South Dakota and extending into Wyoming, USA. Set off from the main body of the Rocky Mountains, the region is something of a geological anomaly—accurately described as an "island of...

 of South Dakota

South Dakota

South Dakota is a state located in the Midwestern region of the United States. It is named after the Lakota and Dakota Sioux American Indian tribes. Once a part of Dakota Territory, South Dakota became a state on November 2, 1889. The state has an area of and an estimated population of just over...

, USA.

Rank	Cave	Length	Location	Year discovered	Associated parks, protected areas
1	Mammoth Cave	627.6 kilometers / 390 miles	near Brownsville, Kentucky Brownsville, Kentucky Brownsville is a city in and the county seat of Edmonson County, Kentucky, United States. The population is 1,000 at the 2000 census. It is included in the Bowling Green, Kentucky Metropolitan Statistical Area... , United States United States The United States of America is a federal constitutional republic comprising fifty states and a federal district...	1791	Mammoth Cave National Park Mammoth Cave National Park Mammoth Cave National Park is a U.S. National Park in central Kentucky, encompassing portions of Mammoth Cave, the longest cave system known in the world. The official name of the system is the Mammoth-Flint Ridge Cave System for the ridge under which the cave has formed. The park was established... , also a World Heritage Site World Heritage Site A UNESCO World Heritage Site is a place that is listed by the UNESCO as of special cultural or physical significance...  and International Biosphere Reserve Biosphere reserve The Man and the Biosphere Programme of UNESCO was established in 1971 to promote interdisciplinary approaches to management, research and education in ecosystem conservation and sustainable use of natural resources.-Development:...
2	Jewel Cave	242 kilometers / 150 miles	near Custer, South Dakota Custer, South Dakota Custer is a city in Custer County, South Dakota, United States. The population was 2,067 at the 2010 census. It is the county seat of Custer County.-History:... , United States United States The United States of America is a federal constitutional republic comprising fifty states and a federal district...	1900	Jewel Cave National Monument Jewel Cave National Monument Jewel Cave National Monument contains Jewel Cave, currently the second longest cave in the world, with just over of mapped passageways. It is located approximately west of the town of Custer in South Dakota's Black Hills...
3	Optymistychna Cave Optymistychna Cave Optymistychna is a gypsum cave located near the Ukrainian village of Korolivka, Borschiv Raion, Ternopil Oblast. , it has 230 km of mapped passageways and is the largest cave complex in Eurasia...	233 kilometers / 143 miles	near Korolivka Korolivka Korolivka is a village in Brodivskyi Raion, Lviv Oblast, in western Ukraine.From 1918 to 1939 the village was in Tarnopol Voivodeship in Poland.... , Ukraine Ukraine Ukraine is a country in Eastern Europe. It has an area of 603,628 km², making it the second largest contiguous country on the European continent, after Russia...	1966	none
4	Wind Cave	216 kilometers / 134 miles	near Hot Springs, South Dakota Hot Springs, South Dakota Hot Springs is a city in Fall River County, South Dakota, United States. As of the 2010 census, the city population was 3,711. It is the county seat of Fall River County... , United States United States The United States of America is a federal constitutional republic comprising fifty states and a federal district...	1881	Wind Cave National Park Wind Cave National Park Wind Cave National Park is a United States national park north of the town of Hot Springs in western South Dakota. Established in 1903 by President Theodore Roosevelt, it was the seventh U.S. National Park and the first cave to be designated a national park anywhere in the world. The cave is...
5	Lechuguilla Cave Lechuguilla Cave Lechuguilla Cave is, as of June 2011, the sixth longest cave known to exist in the world, and the deepest in the continental United States , but it is most famous for its unusual geology, rare formations, and pristine condition....	207 kilometers / 128 miles	near Carlsbad, New Mexico Carlsbad, New Mexico Carlsbad is a city in and the county seat of Eddy County, New Mexico, in the United States. As of the 2010 census, the city population was 26,138. Carlsbad is the center of the designated micropolitan area of Carlsbad-Artesia, which has a total population of 55,435... , United States United States The United States of America is a federal constitutional republic comprising fifty states and a federal district...	1900	Carlsbad Caverns National Park Carlsbad Caverns National Park Carlsbad Caverns National Park is a United States National Park in the Guadalupe Mountains in southeastern New Mexico. The primary attraction of the park for most visitors is the show cave, Carlsbad Caverns...
6	Hoelloch Cave	196 kilometers/ 122 miles	Muotathal Muotathal Muotathal is a municipality in Schwyz District in the canton of Schwyz in Switzerland. The eponymous valley is formed by the Muota river, which joins Lake Lucerne at Brunnen.-Geography:... , Switzerland Switzerland Switzerland name of one of the Swiss cantons. ; ; ; or ), in its full name the Swiss Confederation , is a federal republic consisting of 26 cantons, with Bern as the seat of the federal authorities. The country is situated in Western Europe,Or Central Europe depending on the definition....	1875	none
7	Fisher Ridge Cave System	180 kilometers / 113 miles	near Cave City, Kentucky Cave City, Kentucky Cave City is a city in Barren County, Kentucky, United States. The population was 1,880 at the 2000 census. It is part of the Glasgow Micropolitan Statistical Area.-Geography:Cave City is located at .... , United States United States The United States of America is a federal constitutional republic comprising fifty states and a federal district...	1981	Mammoth Cave National Park Mammoth Cave National Park Mammoth Cave National Park is a U.S. National Park in central Kentucky, encompassing portions of Mammoth Cave, the longest cave system known in the world. The official name of the system is the Mammoth-Flint Ridge Cave System for the ridge under which the cave has formed. The park was established...
8	Sistema Ox Bel Ha Sistema Ox Bel Ha Ox Bel Ha is a cave system in Quintana Roo, Mexico. It is the longest explored underwater cave in the world and ranking no. 4 including dry caves. As of October 2011 the surveyed length is of underwater passages....	179 kilometers / 112 miles	near Tulum, Quintana Roo Quintana Roo Quintana Roo officially Estado Libre y Soberano de Quintana Roo is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided in 10 municipalities and its capital city is Chetumal.... , Mexico Mexico The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...	1996	none
9	Sistema Sac Actun	175 kilometers / 109 miles	near Tulum, Quintana Roo Quintana Roo Quintana Roo officially Estado Libre y Soberano de Quintana Roo is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided in 10 municipalities and its capital city is Chetumal.... , Mexico Mexico The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...	2007	none
10	Gua Air Jernih	174 kilometers / 108 miles	Miri Miri Miri is a city in northern Sarawak, Malaysia, on the island of Borneo. It is the second largest city in Sarawak, with a population of about 300,000, and the government administrative centre of Miri District in Miri Division.... , Sarawak Sarawak Sarawak is one of two Malaysian states on the island of Borneo. Known as Bumi Kenyalang , Sarawak is situated on the north-west of the island. It is the largest state in Malaysia followed by Sabah, the second largest state located to the North- East.The administrative capital is Kuching, which... , Malaysia	1978	Gunung Mulu National Park Gunung Mulu National Park Gunung Mulu National Park near Miri, Sarawak, Malaysian Borneo, is a UNESCO World Heritage Site that encompasses incredible caves and karst formations in a mountainous equatorial rainforest setting... , also a World Heritage Site World Heritage Site A UNESCO World Heritage Site is a place that is listed by the UNESCO as of special cultural or physical significance...

External links

• (List of world's longest caves)