World Facts

The Longest Caves In The World

The Mammoth Cave system in Kentucky, US, is the longest in the world stretching for about 651.8 kilometers.

Caves and their mysterious formations have forever captivated humans and continue to do so today. There are 8 principle types of caves and they each have distinct formation processes. The first type is the solutional cave, which is formed by naturally acidic groundwater slowly eating away at rock, these cracks gradually expand over time. The second type of cave is the primary cave which is created by lava flows. Sea caves are located on coastlines all over the world and have been formed by waves cutting into the sea cliffs. The next common cave type is the erosional cave which, as the name suggests, are formed by erosion of either wind or water. Glacier caves have formed by melting and slow moving ice. Fracture caves are formed when layers of soluble rock dissolve between layers of less soluble rock. Talus caves are less akin to traditional caves, and are a kind of caves within unstable rock piles that are typically found at the bottom of cliffs. Finally, anchialine caves are found on coastlines and contain a mix of salt and freshwater. The following article takes a look at some of the longest caves in the world, where they are, and how they formed.

Longest Caves in the World

Mammoth Cave

By far, the longest cave in the world is the Mammoth Cave in Brownsville, Kentucky, US. This cave is 405 miles long!! Mammoth Cave is located in a National Park and visitors can tour the inside. Long ago, Native Americans used some areas of the cave as burial sites. The interior is home to several species of bats, some of which (such as the Eastern Small-footed bat) have gone down in numbers, and the park is currently taking on conservation efforts.

Sistema Sac Actun-Dos Ojos

The second longest cave in the world is the Sistema Sac Actun and Dos Ojos at 208.15 miles. This natural wonder is located in Tulum in Quintana Roo, Mexico. These cave systems are underwater and run along the Caribbean shore and have two types of tunnels running through it. The tunnels run parallel and perpendicular to the coastline. Tourists can snorkel and scuba dive in some areas of the caves.

Jewel Cave

Number 3 on the list is 180-mile long Jewel Cave located in Custer in South Dakota, US. This cave was discovered in 1900 when two men felt a cool air escaping through a small hole in the ground. They widened the hole and found a cavern filled with calcite crystals, hence the name. Of the many formations inside, the rarest is a hydromagnesite balloon which is formed when gas fills the substance caused by precipitation of the mineral magnesium carbonate hydroxide.

Other Long Caves

Those caves listed above are the top 3 longest in the world. There are many more worth mentioning, all over 100 miles long. They are located all over the world and include Sistema Ox Bel Ha in Tulum, Quintana Roo, Mexico at 159.75 miles long, Optymistychna Cave in Korolivka, Ukraine (146.64 miles), Wind Cave in Hot Springs, South Dakota, US (142.72 miles), Lechuguilla Cave in Carlsbad, New Mexico, US (138.31 miles), Clearwater Cave in Miri, Sarawak, Malaysia (133.78 miles), Fisher Ridge Cave System in Brownsville, Kentucky, US (124.58 miles), and Hölloch in Muotathal, Switzerland (124.52 miles).

Biodiversity, Anthropology, and Tourism

Caves and their uses are typically associated with primitive people and while that seems to be unimportant for modern society, it actually is important. Being able to study the fossils, human remains, and tools that have been left behind allow researchers to have a better understanding of human ancestry. Caves are also home to a wide variety of flora and fauna, some of which live their entire life cycle inside. Due to the delicate nature of cave ecosystems, many of the animals located inside are endangered such as Tooth Cave spiders and Gray bats. Caves are also important to the economies where they are located. They are a popular tourist destination and bring tourists from all over the world to visit. The visitors don’t only visit the caves but spend money in local restaurants and hotels thereby boosting the local economy.

The Longest Caves In The World

RankCave SystemLength (in km)Location
1Mammoth Cave651.80Brownsville, Kentucky, United States
2Sistema Sac Actun / Sistema Dos Ojos335.00Tulum, Quintana Roo, Mexico
3Jewel Cave289.80Custer, South Dakota, United States
4Sistema Ox Bel Ha257.10Tulum, Quintana Roo, Mexico
5Optymistychna Cave236.00Korolivka, Ukraine
6Wind Cave229.70Hot Springs, South Dakota, United States
7Lechuguilla Cave222.60Carlsbad, New Mexico, United States
8Clearwater Cave/Gua Air Jernih215.30Miri, Sarawak, Malaysia
9Fisher Ridge Cave System200.50Brownsville, Kentucky, United States
10Hölloch200.40Muotathal, Switzerland

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