Our planet's surface is covered with natural structures that rise to incredible heights or carve to treacherous depths or caverns that stretch far beneath the ground we walk on in this dark subterranean world there are strange creatures terrifying squeezes and events that can't be explained here are the top 15 most scary tunnels and caves
number 15 gomantong caves sabah malaysia located within the gomantang hill of sabah malaysia the gomantong caves are a vast network of caverns that have formed over thousands of years in the limestone bedrock inside there's virtually every cave feature you can think of including countless stalactites and slag mites as well as natural pools labyrinthine tunnels and sheer limestone walls that are in places as high as 300 feet it's one of the most incredible known cave systems on earth but beyond the network itself the thing that truly makes it frightening is the wealth of animal life that lives inside the caves are probably most famous for being the home to a colony of an estimated 300 000 wrinkle-lipped freak-tailed bats whose nightly flights from the cavern are a popular tourist attraction but means the floor is unbelievably slippery because of the thick covering of guano even if you're able to handle trudging through that you'll also need to contend with the many millions of malaysian cockroaches various species of snakes and a number of type of scorpions and crabs and most worryingly of all the giant scutiguera centipedes a species that grows up to three inches long and can deliver a nasty poisonous bite [Music]
number 14 wind cave south dakota wind cave national park in south dakota was first established in 1903 by president roosevelt around what is currently the seventh longest known cave network in the world and by far the densest system on earth so far more than 154 miles of passageways have been explored and there's plenty more still to go the cave network actually exists on three different levels because of the way that it's carved through different layers of bedrock and it's also unlike any other cave because of the prevalence of unusual calcite formations known as boxwork which account for 95 percent of all the known examples of these worldwide the thing that's particularly unnerving about moving through these underground cavities is what gives the system its name and it's the way that air passes through there's such a huge volume within the network that when air pressure changes above ground a noticeable current can be felt either moving into or out of the caves as the weather systems in south dakota are renowned for rapid changes it can almost feel as if you're standing inside a breathing creature it's also perhaps no surprise that the region was considered a sacred site for the lakota people who believed it to be a passageway to the underworld
number 13 cave of the sybil italy from the aeneid which told of the trojan wars and the writings of virgil to the legends of the last roman king tarkinius superbus the works of ovid painting by michelangelo on the ceiling of the sistine chapel and even the poetry of t.s eliot a legendary greek oracle known as the sybil has made appearances throughout history said to be a guide to the underworld but also having predicted the rise of rome been able to grant wishes and possess the secrets to eternal life the story's told of how she lived in a cave with more than a hundred openings somewhere near the settlement that is now known as naples in italy based on these tales people have been searching for the sybil's cave since the middle ages but in 1932 an archaeologist who was responsible for much of the work conducted at pompeii made an astonishing discovery in monteticama there was an entrance to an elaborate man-made cave that's believed to have been built around 2600 years ago by etruscan slaves under the orders of the romans with countless entrances it measures 430 feet long and just over 16 feet high and while the sybil of legend has yet to be seen you can't help feel as if you're traveling to the underworld which the greeks believe was located beneath the nearby lake awareness
number 12 akton tunichill muknow belize south america is covered in vast cave networks that have been formed over tens of thousands of years the ancient cultures that once lived there saw them as important connections with powers that they believed in and specifically as roots to the underworld each one is unique with various ancient artifacts found across the continent but perhaps the most archaeologically valuable and creepy is known as the akhtun tunichil muknal or atm for short it can be found within the tapir mountain nature reserve in belize and it's made up of a main cave system that's approximately three miles long along this stretch there's a number of widened caverns that were used by the maya within them are countless examples of ceramics and stoneware that were for ceremonial use and most frightening of all there's also several human remains that have calcified into the floor because they are in some cases more than a thousand years old the most famous of these is known as the crystal maiden which is an almost perfectly preserved skeleton of a seven-year-old male who had been sacrificed in the cave and whose bones are now sparkling because of the calcification process with further evidence of the caves being widened to create more space and even the construction of altars and structures designed to cast the shadows of animals and people onto the walls it was one of the most sacred sites of the maya and in modern times one of the most ominous cave networks ever found
number 11 the hellfire caves england also known as the west wickham caves the hellfire caves in buckinghamshire england is a series of man-made tunnels and caverns that were excavated in chalk and flint bedrock between 1748 and 1752 reaching more than 850 feet underground they were created to hold meetings of the hellfire club an exclusive group for members of high society and took design inspiration from italian greek turkish and syrian architecture from the time featuring a number of caves as well as a river and an inner chamber that sits beneath a church on the hill above where the tunnels were dug the club itself had dissolved by 1766 and the tunnels became involved with more sinister uses to this day there are frequent reports of paranormal activity throughout the entire complex such as the ghost of a young maid who died down there and several other people who met a grisly end within the tunnels these experiences became so famous that for more than half a century the caves have been one of the most popular tourist attractions in the region with every visitor hoping to hear the mysterious echoes and see the specters for themselves
number 10 optimistic cave ukraine located near the village of korolevka in ukraine the optimus teachnot cave is the fifth longest known cave network on earth amazingly it was only first discovered in 1966 and so far more than 140 miles or 230 kilometers of tunnels have been mapped the whole formation lies beneath a gypsum deposit that's more than 20 million years old and it's around 98 feet thick and because of the type of rock that it had formed in the tunnels of the cave are incredibly tight measuring no more than ten feet wide and five feet tall with constant water flowing through the system it's often caked full of mud too making navigation difficult and it's known as a maze cave on top of the gypsum above the cave is a layer of limestone that over thousands of years have been slowly eroded and deposited within the tunnels which has resulted in the creation of a series of calcite speleothems and other structures like gypsum rosettes and crystal mounds those brave enough to venture into the depths are treated to one of the most spectacular subterranean views anywhere on earth so far only around 50 expeditions have ever set foot inside
nine moaning cavern california the moaning cavern in the calaveras county of california was first discovered in recent times by gold prospectors in 1851 but has long been known by local communities as a particular mysterious place it gets its name because of the ominous sounds that used to emanate from the cave entrance because of the way that the wind would channel through the formation and despite the fact that this is no longer as prominent after works were conducted to expand the opening to allow tourists to enter there's still plenty more inside to give you the creeps reaching a maximum depth of 410 feet there's a series of huge chambers that are traversable with a series of staircases but historically were incredibly dangerous before safer methods of access were built it's because of these that the cavern has become an important archaeological site and it's where the oldest remains to have so far been discovered in america were found dating back to more than twelve thousand years as well as these countless other human bones have been uncovered some of which are only a few decades old proving that despite its popularity as a tourist destination there's a real and present risk of entering
number eight order cave russia the incredible order cave is a series of tunnels and caverns that stretch beneath the western ural mountains in russia with the entrance positioned on the shore of the congo river near the locality of orda it's around 3.2 miles long three miles of which is completely submerged carved into the gypsum bedrock over tens of thousands of years it's one of the longest underwater caves ever discovered and by far the longest underwater gypsum cavity because of the unique mineral makeup of the surrounding area the water inside is exceptionally clear with a typical visibility of more than 50 yards and makes it a fantastic place for underwater photography to capture the formations that lie within and to study how cave systems like this develop in the first place and continue to evolve despite the clarity this is a place that only the most experienced of cave divers should venture because of the unpredictability of the currents and how often large rocks and boulders can detach and block the tunnels and because of these dangers it's somewhat of a local legend people in the nearby community talk of the lady in the orda cave who was believed to live in the tunnels and will often try to dissuade anyone else from entering to prevent them from getting lost with no way out
number seven cave of the crystals mexico in search of the most valuable materials on earth miners often drill to incredible depths and are the first to discover incredible formations the nika mind in chihuahua mexico has long been a profitable lead zinc and silver mine but in the year 2000 something unbelievable happened while digging around 980 feet beneath the surface two brothers broke through a wall and uncovered a huge chamber within the limestone rock that was filled with gigantic selenite crystals known as the cave of the crystals it contains some of the largest examples of these formations ever discovered with some of the crystals measuring up to 37 feet long and believed to weigh as much as 12 tons the cave itself is around 358 feet long and it's one of the most awe-inspiring subterranean places in the world the only problem is that the conditions that have resulted in its creation mean that it's incredibly dangerous for humans to enter with a humidity of between 90 and 99 and continuous temperatures of around 136 degrees fahrenheit or 58 degrees celsius you'd only be able to last 10 minutes in there unaided because of this inhospitable environment very little investigation of the cave was possible and the cessation of mining activities in the region has meant that without active water pumps the cave is now completely flooded rendering it completely inaccessible what it proves however is that there's a mysterious world lying deep beneath us and perhaps one day more caverns like this will be found
number six the bell witch cave tennessee in 1804 john bell and his family purchased a farm in adams tennessee a move that according to local legend displaced a witch called kate batts she is said to have fled to a cave that was on the property which stretches around 490 feet beneath the ground and shortly after the family began to experience a series of horrifying events strange animals began appearing on the farm a few years later john bell soon became extremely sick with choking fits and a strange illness and the youngest daughter betsy suffered scratches all over her body the witch supposedly threatened the family a number of times and it was only once the farmer had died that the hauntings ended in her parting words the witch said that she would return at some point in the future and fled back to the cave now known as the bell witch cave the opening has become a popular tourist site for those wanting to explore the paranormal and in the past 150 years there have been numerous reports of strange sensations and observations by those brave enough to enter quite how much truth there is to any of this is up for debate but there's no denying that thanks to the stories it's a frightening place to enter
number five pleura cave norway which is known locally as pluragrata is by far the deepest cave in northern europe it's in the rama region of norway and was only first explored in 1980 after having been revealed after the construction of a nearby dam reduced the water flow in the area lying beneath the scandinavian mountains it's almost entirely filled with water although there are several caverns within it that are dry in 2013 a team of explorers found that it actually connects with another nearby cave system and that it reaches a maximum depth of 1300 feet or almost 400 meters containing a series of stunning marble formations it's no surprise that the pleura cave has become a popular site for cave divers but the conditions inside mean that it's particularly dangerous to venture into with tight passageways extremely sharp stones that can easily puncture your equipment and depths that require several decompression stops to return to the surface only highly experienced divers are allowed anywhere close even with these precautions a number of accidents have happened there since its discovery with at least three people known to have died after getting lost and a number more suffering extensive injuries and decompression sickness
number four krubera cave georgia reaching deep beneath the arabica massive in nagra mountain range of georgia in eastern europe the kubera cave is currently the second deepest known natural underground system on earth the entire region is actually full of cave networks that carve far beneath the surface because of the way that the limestone bedrock originally formed and so far explorers have ventured through tunnels to a depth of 7 200 feet beneath the cave entrance while adventurers have known and charted the cave since the early 20th century the main work in detailing just how vast it is took place in the past few decades it's so extensive that this simply isn't a day trip those who reach the lowest sections will spend up to a month underground the cave has a series of camps in a similar way to those that are positioned for climbers on the tallest mountains on earth with narrow passageways large sections underwater and regular tectonic movements it often requires an entirely different route to leave the cave than the one that was taken to climb down it's also an extremely strange environment which is teeming with various species of spiders crustaceans pseudoscorpions and plenty more that aren't found anywhere else as well as the deepest terrestrial animal to have ever been discovered type of beetle that was found at a depth of 6 500 feet beneath the entrance it's an incredibly important place for research into the subterranean world but it's certainly not suited to inexperienced cavers or to anyone who feels uneasy in confined spaces for extended periods of time
number three gorner glacier caves switzerland found on the western side of the monterossa mountain massif between italy and switzerland the gorner glacier is the second largest glacial system in the alps measuring seven and a half miles long and up to a mile wide as is the case with most glaciers it's constantly moving at a very slow pace with ice melting at its extremities but because of the way that it feeds into a nearby lake it also melts at the base and inside which creates an ever-changing network of ice caves within the entrances to the caves are known as moulins and they're often near vertical shafts that lead from the surface of the glacier and require specialist equipment to attempt the descent needed to get inside once explorers have done so though they're in for a real treat because with the way that the light passes through the ice the caverns take on a spectacular blue glow and are filled with countless natural ice formations anyone who enters has to keep their wits about them however because any journey inside a glacier is fraught with danger the parts that are submerged require thick dive suits to endure the freezing temperatures and even then there's a limit to how long someone can survive furthermore just a slight change in temperature outside the cave can cause chambers to collapse or huge water flows to fill the caves in an instant something that could potentially spell disaster for anyone who's inside at the time [Music]
number two mammoth cave kentucky if there's ever a cave that you could quite easily get lost in then it's the mammoth cave in kentucky in the united states it's by far the longest known cave system on earth and after a recent investigation found further voids contains at least 420 miles of tunnels that's roughly equivalent to the distance between new york and north carolina but all of it journeys deep underground and is virtually entirely pitch black near the entrance there are facilities to welcome visitors to the first stretch of the cave and these contain wooden walkways and artificial lighting something that attracts as many as 2 million people a year to see the incredible natural formation and the more than 130 different wildlife species that call the cave home once you get beyond these parts however the caves become far more treacherous long winding tunnels with huge vertical climbs tight squeezes crawl ways and endless flowing water and mud mean that only the most experienced cave explorers are able to truly venture into the depths it's such an ominous place that the mammoth cave was the inspiration for hp lovecraft's story the beast in the cave evidence has been found that prehistoric people used the cave as far back as 4 000 years ago to bury their dead in the early 19th century slaves were sent to mine salt in the cave where many perished and one of the caverns was used to hold tuberculosis victims meaning with the number of people who died down there there have been a number of ghost sightings which are still regularly reported to this day [Music]
number one the shaft australia in 1938 a farmer was traveling by horse across his land near mount gambier in south australia when his steed suddenly tripped on a strange object on the ground after looking closer he realized that a small sinkhole had opened up and he saw that there was a cavern beneath that was far deeper than he was able to measure word of the mysterious shaft began to spread and divers from around the country traveled to the area where they'd squeeze through the tight opening to enter a spectacularly huge crystal clear water cave which is up to 460 feet across and seemingly bottomless with several passageways branching off of it it's an explorer's paradise but one wrong move can spell disaster despite hundreds of groups having swum in the water tragedy struck in may of 1973 when a group of eight divers ventured in later that day only four would return after the group decided to leave the sun-lit main chamber into one of the side tunnels after stirring up the silt it was impossible to see and their air ran out before they were able to find the way out it's a reminder of just how dangerous cave diving can really be and since then restrictions have been put in place to try to ensure no one else meets the same fate in the shaft ever again watch our nature playlist for more top 15 videos about beautiful nature sit back relax and binge watch all of our best nature videos