General description
Every year there are reported exciting discoveries of new caves and discoveries of new qualities such as cave paintings in the ones known before. But there still is a feeling that our knowledge covers just a small part of all these monuments of nature.
Though, those which we know offer a surprising diversity of unusual features and impressive sights.
Contents
Definition
Stone curtain in Postojna Cave, Slovenia.
Bruno Girin, Flickr / CC BY-SA 2.0
Cave is natural underground space which is large enough for human to enter.
As a separate subcategory there are included also sinkholes - large natural depressions or holes, which for most part represent collapsed caves.
Criteria
Category includes caves with outstanding characteristics such as large size, significant geological, biological or archaeological values.
Formation
Fairly solid rock is required to have rigid cave walls and ceiling. Several geologic processes can create large hollows in such solid rock. Most common ones are:
- Dissolution - hollows are created by the flow of water (in most cases) or gases. Process of solution is facilitated by the naturally occuring acids in groundwater. This is the most frequent cave formation process which for most part takes place in limestone, dolomite, marble, gypsum and other comparatively easily soluble rocks. Dissolved minerals in hollows form diverse interesting speleothems - stalactites, stalagmites, columns and also beautiful crystals. Countless caves have beautiful stalactite and stalagmite formations and many show caves are marketed as being the most beautiful ones. Wondermondo will not judge which is the most beautiful one but few will object that Lechuguilla Cave (New Mexico, United States), Phong Nha Cave (Quang Binh Province, Vietnam) or Kap Kutan cave (Lebapp, Turkmenistan) are gorgeous. If there is enough time, water can dissolve even quartzite - material considered to be insoluble. The longest known quartzite cave is the 16 kilometres long System Roraima Sur (Bolivar, Venezuela).
- Volcanic proccesses form several kinds of so called primary caves - caves which form together with the surrounding rock. Lava tubes are created in conditions where hot lava stream gets a harder crust which remains after the lava flows away. Sounds impossible but such proccess have created even such cave as Kazumura Cave (Hawaii, United States) which is 65.5 kilometres long!
- Erosion processes of the sea waves and streams, but sometimes even wind, often create short caves. Sea caves often have beautiful lighting - only blue rays of the sunlight remain after going through the layer of seawater (Blue Grotto in Capri, Italy).
Many caves are formed otherwise - by glacial processes, earthquakes, biological processes - even by elephants (Kitum Cave in Kenya).
Values
Caves can be unique in several ways: most often due to their geological, biological and archaeological values.
Geological values
Many caves are adorned with diverse speleothems - specific rock and mineral formations seen only in caves and created by mineral solutions sedimenting the dissolved minerals in cave. Diversity of speleothems is very high and from time to time there are discovered new fantastic forms. Most common speleothems are stalactites, stalagmites, columns and flowstones. Sometimes such speleothems can reach incredible size: the tallest stalagmites can reach 70 metre height (Zhijin Cave in Guizhou, China).
There are also very exotic and rare speleothems such as:
- Cave pearls - limestone balls up to 15 centimetres in diametre. The floor of Gruta de las Canicas (Tabasco, Mexico) is covered with some 200,000,000 cave pearls! Cave pearls are beautiful - sparkling white or with a marble texture.
- Cave ballons - real ballons from minerals! Ballon is made of hydromagnesite and moonmilk (fine, white pasta of carbonate material) and filled with gas.
- Cave showerheads - hollow cones attached to the ceiling of the cave with the narrow end. As if to justify its name one such showerhead in Deer Cave (Sarawak, Malaysia) is the source of shower - waterfall.
- "Champignons" - opal formations of microbial origin in quartzite caves (Venezuela). These weird formations are up to 1 metre across. Quartzite caves in tepuis of Venezuela are known to have several kinds of otherworldly formations, weird symbiosis of minerals and microorganisms.
Cave environment is very beneficial for the formation of crystals. The largest crystals ever found are up to 12 metres long and 55 tons heavy, beautiful translucent crystals of gypsum in the Cave of the Crystals (Chihuahua, Mexico). Often crystals in caves form very beautiful and unusual formations such as white, intricate "trees" of aragonite crystals or gypsum flowers.
Caves have lots of other interesting geological characteristics such as unique minerals, for example sveite is found in Autana Cave (Venezuela), archerite is found only in caves where are bat guano deposits.
Biological values
Cave insect in Mammoth Cave, United States.
Beatrice Murch, Flickr / CC BY 2.0
The specific cave environment provides shelter for certain species adjusted for more or less permanent life in cave. Scientists have specific names for several groups of cave dwellers:
- Trogloxenes use caves but they need to leave caves periodically to survive, e.g. to get food. Typical trogloxenes are bats. Bracken Bat Cave (Texas, United States) with some 20 million bats is considered to have the largest bat colony of the world.
- Troglophiles are attracted by the caves due to cave environment, but survive in other conditions as well. Famous troglophile is New Zealand glow-worm (Arachnocampa luminosa). Larvae of this small insect attach at the ceiling and walls of many caves and emit blue-green light. This creates unforgettable sights in such caves as Waitomo Glowworm Cave (Waikato, New Zealand).
- Troglobites - animals living only in caves and fully dependant on cave environment. This is very specific group of animals well adapted to a life in total darkness, limited food supply and narrow space. If animal is living in cave waterbodies, he could be called also stygobite.
Olm (Proteus anguinus). Photo by Ranko Tomić, Wikimedia Commons, CC-BY-3.0
Troglobites are unique organisms adapted to specific life conditions and high isolation. Cave dwellers can be slow and live very long lives - up to 175 years, they often do not have eyes but other senses are heightened. Hundreds of species of troglobites are found only in one cave and not anywhere else. So far there are known approximately 7,700 species of troglobites but further investigations could increase this number several times.
The largest known troglobite is Black Proteus (Proteus anguinus parkelj) living in few caves of Slovenia. It is up to 35 centimetres long.
The highest cave biological diversity is observed not in tropical regions but in Europe. Most biodiverse is Sistema Postjna-Planina (Notranjsko-kraška, Slovenia) with 84 species of cave dwellers. Unique monument of nature is Movile Cave (Constanţa County, Romania) with 33 species of animals found only in this cave.
Microorganisms in some caves and also sinkholes create unique conditions. Thus the highly unusual Black Hole of Andros (South Andros, Bahamas) is a water filled sinkhole where at the depth of 18 metres is a dark purple layer of toxic sulphur bacteria. In this layer of bacteria due to biochemical processes the water temperature increases up to 36°C. In Venezuelan quartzite caves microorganisms create unusual opal formations - dendrites, "Champignons" and also unusual stalactites.
During the ice age several species of large animals in Europe and Americas found that caves provide suitable habitat in harsh climatic conditions. Developed such species and subspecies of large animals as cave bear (Ursus spelaeus), cave hyena (Crocuta crocuta spelaea), Balearic cave goat (Myotragus balearicus). Evidence of these and many other extinct animals is found in many caves around the world, notably Peştera Urşilor (Bihor County, Romania) with remains of some 140 cave bears.
Archaeological values
The history of the development of human has been well preserved in the caves of the world. Sterkfontein Caves (Gauteng, South Africa) contain remains of some 500 early hominids up to 3.3 million years old. Caves contain remnants of extinct human species such as Neanderthals (Homo neanderthalensis) whose last refuge seems to be the southern Iberian peninsula. Here in Gorham's cave (Gibraltar) have been found the most recent known, circa 30,000 - 24,500 years old remnants of Neanderthals.
Liang Bua cave, Flores, Indonesia.
Rosino, Flickr / CC BY-SA 2.0
Most recent another species of human have been found in Liang Bua cave (Flores, Indonesia). This man, Homo floresiensis, went extinct some 12,000 years ago, although there is possibility that these small people lived up to recent times.
Caves contain valuable artwork of prehistoric man such as the oldest known artwork - 70,000 years old engraved pieces of ochre (Blombos cave in Western Cape, South Africa) and the oldest sculpture in the world - 35 - 40 thousand years old "Venus of Hohle Fels" (Hohle Fels in Baden-Württemberg, Germany). Petroglyphs of Bhimbetka Caves (Madhya Pradesh, India) might be even 290 - 700 thousand years old.
Conditions in caves are beneficial for preserving artwork and there are known many hundreds of caves with prehistoric paintings in the whole world. Many cave paintings show that tens of thousands years ago inspiration and skills of artists did not differ too much from that of contemporary artists.
Neolithic petroglyphs in Edakkal Caves, India.
Deepak A.B., Flickr / CC BY 2.0
The oldest known cave art comes from Fumane Cave (Veneto, Italy) where barely discernible drawings on the pieces of rocks are circa 32,000 - 36,500 years old. Chauvet Cave (Ardèche, France) has 30,000 - 33,000 years old drawings and here the quality of artwork is already very high. Some of the best monuments of cave art in the world are in Cave of Altamira (Cantabria, Spain) and Lascaux (Dordogne, France). Unusual and well matured artistic style is represented in Laas Gaal (Togdheer Region, Somalia). Great 9,000 years old stencil art is represented in Cueva de los Manos (Santa Cruz, Argentina), even more impressive stencils were made by ancient Aborigenes in Cathedral Cave (Queensland, Australia). Unusual are the 6,000 - 8,000 years old pictograms in Edakkal Caves (Kerala, India).
Numerous important archaeological finds have been made in Central American caves. Circa 1,200 - 900 BC have been made Olmec influenced paintings in Juxtlahuaca (Guerrero, Mexico). Maya culture has left important artefacts in sacred wells (cenotes) such as the Sacred Cenote (Quintana Roo, Mexico). Naj Tunich (Peten, Guatemala) - former Mayan ceremonial cave - contains diverse important artefacts: petroglyphs, paintings, ceramics, burials.
Hidden and fragile
Selenite flowers in Mammoth cave, United States.
Navin75, Flickr / CC BY-SA 2.0
Caves in a way are "hidden monuments" because nearly any cave contains very fragile values which are easily lost through unorganised tourism and vandalism.
We can be sure that in every single country, where are found caves, local speleologists (cave explorers) know a huge lot more than is written in tourist guidebooks. But we should not complain about this: unfortunately there is no other way to preserve cave art, fragile crystals and unique, delicate animals living in caves. It feels much better to know that they exist somewhere than to experience a loss of values due to the faulty nature of human.
Outstanding caves
Here are selected some of the most surprising and interesting caves of the the world, arranged by the part of the world and in an alphabetic order.
Contents
Europe
- Cave of Altamira - Cantabria, Spain. Cave with some of the best cave paintings in the world, mostly polychrome paintings of wild mammals, 18 - 14 thousand years old.
- Chauvet Cave - Ardèche, France. Cave contains the oldest known cave paintings in world, made 33 - 30 thousand years ago. In hundreds of drawings shown at least 13 species of animals, artistic quality of paintings is very high.
- Cosquer Cave - Bouches-du-Rhône, France. Cave with Palaeolithic paintings. The entrance in this cave is located 37 metres under the sea level and most of the art has been destroyed by the sea. Still some 150 paintings remain, part of drawings is 27,000 years old and part - 19,000 years old.
- Daveli's Cave - Athens, Greece. Since ancient times cave by the followers of Pan and nymphs is used as a worship site. Nowadays popular due to reported paranormal phenomenons.
- Eisriesenwelt - Salzburg, Austria. The largest ice cave in the world. Contains beautiful ice formations, more than 42 kilometres long.
- Għar Dalam - Malta Island, Malta. Cave contains unique remnants of such animals as dwarf elephant, hipopotamus, deer and others, trapped on the island at the end of Ice Age, as well as the oldest human remnants in Malta (7,400 years). Cave paintings include paintings of elephants.
- Hohle Fels - Baden-Württemberg, Germany. Contains archaeological artefacts of world importance, including the oldest sculpture in the world: 35 - 40 thousand years old "Venus of Hohle Fels" as well as 35 thousand years old flutes - oldest musical instruments in world. Remnants of cave bears, mammoths and other animals.
- Shulgantash (Kapova Cave) - Republic of Bashkortostan, Russia. Unique Paleolithic paintings.
- La Marche - Vienne, France. Cave contains 15,000 years old paintings of humans. Drawings are realistic to such an extent (f.e. showing individual people in great detail) that for long time this discovery was considered to be fake.
Aragonite formations, Ochtinská Aragonite Cave in Slovakia.
Photo: Jojo, Wikimedia Commons, CC-BY-SA-3.0 - Lascaux - Dordogne, France. One of the most important cave art monuments in world, containing beautiful paintings of animals and humans, circa 16,000 years old.
- Movile Cave - Constanţa County, Romania. Unique cave ecosystem consisting of 48 species. 33 species are found only in this cave.
- Ochtinská Aragonite Cave - Košice Region, Slovakia. Unique aragonite cave with highly unusual formations.
- Optymistychna cave - Ternopil oblast, Ukraine. Third longest cave in the world and the longest gypsum cave in world. Total length: 230.1 km.
- Sistem Postojna-Planina - Notranjsko-kraška, Slovenia. Circa 25 km long cave system, recognized as the most biodiverse cave system in the world with 84 species of animals (mostly insects).
- Psychro Cave - Crete, Greece. Sacred Minoan cave with beautiful cave formations. Numerous artefacts found, including huge amount of semi-precious stones.
Travertine terraces in Škocjan Caves, Slovenia.
Wikimedia Commons, Húsönd, CC-BY-SA-3.0 - Škocjan Caves - Obalno-kraška, Slovenia. Cave system with numerous unique characteristics: giant, 140 metres deep underground canyon of River Reka, underground travertine terraces, Bronze Age and later temples and Prechristian pilgrimage centre.
- Peştera Urşilor - Bihor County, Romania. Beautiful cave with remnants of some 140 cave bears (Ursus spelaeus) trapped by rock slide more than 15,000 years ago.
- Velebit Caves - Lika-Senj, Croatia. In one of the caves, Lukina Jama, there is the highest unhindered single drop in the world (513 metres). Contains also 553 metres deep pitch - the second deepest in the world. Enormous colony of subterranean leeches.
- Víðgelmir - Borgarfjörður, Iceland. Largest (by volume) lava tube cave in the world. 1,585 metres long cave contains ice formations, evidence of habitation, possibly from the Viking age.
- Vrtoglavica - Goriška, Slovenia. Contains the deepest pitch (single vertical drop) in the world (603 metres).
Asia
- Bhimbetka rock shelters - Madhya Pradesh, India. Group of caves containing rich collection of cave art, up to 9,000 years old. Some of caves have been inhabited for more than 100,000 years.
Cave art in Bhimbetka caves, India.
Raveesh Vyas, Flickr / CC BY-SA 2.0 - Edakkal Caves - Kerala, India. Cave with unusual archaeological monument: 6 - 8 thousand years old petroglyphs which resemble ancient writing.
- Gomantong Caves - Sabah, Malaysia. Well known due to swiftlet nests which are collected in 90 metre height for bird's nest soups. Enormous colonies of bats, dung beetles, centipedes and cocroaches.
- Gua Air Jernih (The Clearwater system) - Sarawak, Malaysia. The longest cave in Asia, total length: 175.7 km.
- Gua Nasib Bagus with Sarawak Chamber - Sarawak, Malaysia. Contains the largest known underground chamber in the world which is some 700 metres long, 396 metres wide and 70 metres high.
- Ignateva Cave - Chelyabinsk Oblast, Russia. Limestone cave with unique archaeological finds including Venus figurine with 28 red dots between her legs (representing menstrual cycle), 6 - 8 thousand years old cave paintings.
- Jeita Grotto - Mount Lebanon Governorate, Lebanon. Beautiful, nearly 9 kilometres long cave with the world's largest stalactite - 8.2 metres long.
- Khoun Xe Cave - Khammouan, Laos. 13,6 km long cave, traversed by the largest cave river in the world. Here are located the largest rimstone pools in the world and here live the largest spiders in the world.
- Krubera Cave (Voronya Cave) - Gagra, Abkhazia, Georgia. Deepest known cave in the world, circa 2,191 metres deep.
- Liang Bua - Flores, East Nusa Tenggara, Indonesia. In the cave (and only here) there were discovered remnants of a newly discovered, extinct species of human - Homo florensiensis.
Ascending from the floor of Majlis al Jinn, Oman. Photo from Wikimedia Commons, CC-BY-SA-3.0
- Majlis al Jinn - Sharquiah, Oman. Ninth largest cave chamber in world in unique setting, available only by abseiling 118 - 158 metres through the ceiling. People live on the top of this enormous chamber which has only 40 metres thick ceiling.
- Paradise Cave (Dong Thien Duong), Hang Khe Ry and Hang Son Doong - Quang Binh Province, Vietnam. Some of the most beautiful caves in the world. Hang Khe Ry Cave has the world's longest underground river (13,969 m) with sandy beaches, contains valuable archaeological artefacts of Champa culture including beautiful ceramic vases. Hang Son Doong Cave contains more than 4 km long passage, which is continuously 90 m wide and up to 200 m high, here are located also unique cave pearls as large as baseballs, as well as green, algae covered gours.
- Cave of Patriarchs - West Bank. Holy site for Jews, Christians and Muslims - according to each religion here are buried Adam and Eve or Abraham or other important persons acting in religious books.
- Puerto Princesa Subterranean River - Palawan, Philippines. 8.2 kilometres long navigable underground river accessible directly from the sea.
- Shanidar Cave - Kurdistan, Iraq. Cave has provided important discoveries regarding Neanderthals, such as the information about their funeral ceremonies, care for injured individuals. One Neanderthal found in cave seems to be killed by a human.
Underground River in Palawan, Philippines.
Donabel and Ewen, Flickr / CC BY 2.0 - Soo Doong cave - Quang Binh Province, Vietnam. The largest cave in the world with enormous, 4.5 kilometres long passage with maximum height 200 metres and width - 150 metres.
- Zhoukoudian - Beijing, China. Famous due to archaeological findings such as one of the first known specimens of another human species - Homo erectus, called also Peking Man, who lived here approximately 200,000 - 750,000 years ago. Cave inhabited also by modern humans in Upper Paleolithic. Remains of numerous extinct animals such as gigantic hyena Pachycrocuta brevirostris.
- Xiaozhai tiankeng - Chongqing, China. Largest sinkhole (tiankeng) in the world, up to 662 metres deep, 625x535 metres across.
Africa
- Apollo 11 Cave - Karas, Namibia. Contains some of the oldest cave art in Africa, created 25,500 - 23,500 BC.
- Blombos Cave - Western Cape, South Africa. Contains the oldest known artwork in the world - at least 70,000 years old engraved pieces of ochre, also 75,000 years old beads of shell.
- Chinhoyi Caves - Mashonaland West, Zimbabwe. Group of legendary, impressive caves with up to 110 metres deep lakes. Extremely high transparency of water where clouds and birds flying over can be seen from 30 metre depth inside the cave lake.
- Kitum Cave and other caves of Mt. Elgon - Nyanza and Western povinces, Kenya. Unique caves in pyroclastic rocks, up to 150 metres long. Possibly created by elephants and other animals digging the salt in caves up to this day. Kitum cave became known worldwide after two people caught the extremely dangerous and deadly Marburg virus in this cave.
Laas Gaal rock art, Somalia.
najeeb, Flickr / CC BY-SA 2.0 - Laas Gaal - Togdheer Region, Somalia. System of caves and shelters with beautiful cave paintings, created 11 - 5 thousand years ago. In this region reported numerous other caves with paintings.
- Sibudu Cave - KwaZulu-Natal, South Africa. Very important Middle Stone age site. Found the oldest known bone arrow and needle (both 61,000 years old) and traces of heat treated gluing of stone and wood (72,000 years ago).
- Sterkfontein - Gauteng, South Africa. The richest site for early hominids in the world. Found remnants of some 500 hominids, mainly Australopithecus africanus.
- Cave of Swimmers - New Valley, Egypt. Contains circa 10,000 years old cave art showing swimming people. Since its discovery serves as a proof for existance of climate changes.
North America
- Actun Tunichil Muknal - Cayo District, Belize. Important Mayan archaeological site with remains of a teenage girl. Her bones by natural processes have been covered with sparkling calcite crystals.
Skeleton in Actun Tunichil Muknal, Belize.
Peter Andersen, Wikimedia Commons, SA-BY-SA-3.0 - Bermuda's Caves - Bermudas. Biodiversity hotspot: in more than 150 caves of Bermudas there are more than 60 species of underwater animals, most of them endemic, representing an eclectix mix of descendants from European, Atlantic, Pacific and deep sea animals.
- Black Hole of Andros - South Andros, Bahamas. Round lake - sinkhole with a layer of violet jelly layer of bacteria at 18 metres depth. Due to this the upper layer of water in this sinkhole is heated up to 40 degrees C°.
- Cave of the Crystals - Chihuahua, Mexico. Cave with giant selenite crystals up to 11 metres long.
- Dean's Blue Hole - Long Island, Bahamas. World's deepest sinkhole in the sea, 202 metres deep and only 25 - 35 metres across.
- El Zacatón sinkhole - Tamaulipas, Mexico. World's deepest water-filled sinkhole, 339 metres deep sinkhole with 319 metres deep lake. Floating islands in the lake.
- Great Blue Hole - Belize District, Belize. Perfectly round undersea sinkhole, 300 metres across and 125 metres deep.
- Jewel Cave - South Dacota, United States. The second longest cave in the world, total length: 233.08 km.
- Juxtlahuaca and Oxtotitlán - Guerrero, Mexico. Two caves with unique ancient Olmec paintings made 900 - 500 BC.
- Lechuguilla Cave - New Mexico, United States. 203 kilometres long cave, one of the most decorated and beautiful caves in the world with unique kinds of speleothems, such as: hydromagnesite ballons, U-loops, up to 6,1 metres long gypsum hairs.
- Loltun Cave - Yucatán, Mexico. Cave with some of the best Mayan cave paintings as well more ancient carvings and remnants of prehistoric animals hunted by Paleoindians.
- Mammoth Cave System - Kentucky, United States. The longest cave system in the world (590.6 km).
- Naj Tunich - Peten, Guatemala. Unusual Mayan archaeological monument in a cave, extremely rich with artefacts. Buildings inside the cave, the only known masonry tombs of elite inside a cave known to science, petroglyphs, inscriptions.
- Pomier Caves - San Cristóbal, Dominican Republic. Series of 55 caves containing the largest collection of ancient rock art in Caribbean, created 2,000 years ago by Taíno, Carib, Igneri people. Approximately 6,000 charcoal drawings and etchings.
- Poza Seca - Tamaulipas, Mexico. One of the unique travertine capped sinkholes in Sistema Zacatón: formerly open sinkhole has sealed itself with a limestone lid. Most likely it hides unknown life forms, not investigated.
- Sacred Cenote - Quintana Roo, Mexico. Human sacrifice site of the ancient Mayan Chichen Itza city. In deposits discovered huge amounts of gold and jade artefacts as well as human remains.
- Sótano de las Golondrinas (Cave of Swallows) - San Luis Potosí, Mexico. The largest cave shaft in the world - enormous 49 x 62 metres wide hole, 372 metres deep. Famous due to a group of green parrots who have to fly ascending in circles around the cave until they get out of it.
- Systema Ox Bel Ha - Quintana Roo, Mexico. World's largest known underwater cave system, total explored length - 180 km.
- Systema Sac Actun - Quintana Roo, Mexico. Another world's largest known underwater cave system, total explored length - 176 km.
South America
- Abismo Guy Collet - Amazonas, Brasil. The deepest cave in South America and deepest quartzite cave in the world, 671 metres deep.
- Cueva Fell and Pali Aike - Magallanes and Antártica Chilena, Chile. Lava tube where circa 12,000 - 8,000 BC lived ancient Patagonians. Remnants of ancient giant Patagonian fauna.
Cueva de las Manos, Argentina.
Marian Ocecowski, Wikimedia Commons, CC-BY-SA-3.0 - Cueva de las Manos - Santa Cruz, Argentina. Famous due to paintings of hands on its walls made some 9,000 years ago, often stencilled. Numerous other drawings as well.
- Serra do Ramalho - Bahia, Brasil. Group of large caves with high cave biodiversity, containing endemic species of animals, including endemic fish.
- Sima Aonda - Bolivar, Venezuela. 383 metres deep, ancient quartzite sinkhole, with waterfall and stream flowing through it.
- Sima Humboldt and Sima Martel - Bolivar, Venezuela. 314 and 248 metres deep, ancient quartzite sinkholes located on the top of forested table-top mountains and containing patches of isolated, primeval rainforest on their bottoms.
- Sistema Roraima Sur - Bolivar, Venezuela. Longest known cave system in quartzite, contains numerous unique geological formations. Investigated up to 16,140 metre length.
- Tambolic caves - Amazonas, Peru. Caves with more than 10,000 cave paintings more than 6,000 years old.
- Toquepala Caves - Moquegua or Tacna, Peru. Cave with expressive group of circa 7,650 years old paintings.
Australia and Oceania
- Kazumura Cave - Hawaii, United States. The longest lava tube in world, 65.5 km.
- Koonalda Cave - South Australia, Australia. 20,000 years old cave art covering thousands of square meters.
- Minyé sinkhole and cave - East New Britain Province. One of the largest and most impressive tiankengs (giant sinkholes) in world, located in exotic jungle and crossed by powerful underground river. Up to 510 metres deep, 350 metres across, volume - 26 million m³. It continues as a cave system. Explored length of cave passages is 5,421 m, maximum depth - 468 m. Contains one of the largest cave rooms in the world - Tuké room, 240 m long, 200 m wide and 130 m high.
- Nanumanga Fire Caves - Nanumanga, Tuvalu. Undersea caves, approximately 37 - 46 metres under the sea level. Caves show signs of fire left by prehistoric people. This find contradicts with the current assumptions of the sea level changes.
- Waitomo Glowworm Cave - Waikato, New Zealand. The best known glowworm cave, adjusted for the needs of tourism. In many places in this cave (as in most New Zealand caves) walls are covered with larvae of glowworms (Arachnocampa luminosa) emitting blue-green light.





26 July 2010 Gatis Pāvils