Many of us never think about the fact that down below us, beneath the world of light and civilization lurks another world altogether, one of cold, eternal darkness, a stranger to the sun. Down in these black depths of the earth exist vast caverns and caves that most are not even aware of, and there are reports that these are not necessarily devoid of life. Indeed, it seems that there possibly exist strange monsters down in the deep places of the earth, which shuffle about and stalk the never-ending night, even once in a while poking up from their hidden lairs into our world to baffle and terrify.

When talking about underground monsters, something one might wonder is whether there are any sorts of mystery giant worms prowling about out in the wilds under our feet, and the answer is, according to some reports, yes. If you’ve ever seen the movie Tremors, then you might know what I mean, and there is said to be a cryptid in the remote areas of South America that is very much like this. Called the Minhocão (literally “big earthworm” in Portuguese), this creature is described as an absolutely enormous worm-like beast measuring from 75 feet up to an astounding 150 feet long, which burrows through the earth and feeds on anything it can catch walking above. Some added details are that it has black skin, small eyes, a pair of tentacles on its mouth or head, and an array of large, sharp teeth within its maw. The creature is so massive that it is believed to leave huge trenches in its wake, which sometimes collapse to send houses and other structures tumbling down into the ground, and there are various reports of it sucking animals down into the earth, such as dogs, cats, and even livestock such as cows.

One of the first accounts of the Minhocão appeared in the 1800s in an article in the American Journal of Science, in which naturalist Auguste de Saint-Hilaire brought forth some alarming cases of cattle being pulled into the earth or underwater by some vast worm in the province of Goyaz, often right before the eyes of startled witnesses. In 1877, the German publication Zoologische Garten featured an article by zoologist Fritz Müller, who gave an 1840 account of one of the beasts at Rio dos Papagaios in Paranà State thus:

A black woman going to draw water from a pool near a house one morning ... saw a short distance off an animal which she described as being as large as a house moving off along the ground. ... In the same district a young man saw a huge pine suddenly overturned ... he found the surrounding earth in movement, and an enormous worm-like black animal in the middle of it, about twenty-five meters long, and with two horns on its head.

In addition to numerous instances of strange trenches dug through the ground and anomalous trembling of the earth in conjunction with sightings of giant worms, the article also mentions a 1849 report of a dead Minhocão that was purportedly found stuck in some rocks near Arapehy, Uruguay. The carcass was described as having rough skin like tree bark and scales that those of “an armadillo.” In 1870 Müller claimed that there had been a sighting at Lages, Brazil, when a Francisco de Amaral Varella apparently saw a massive, legless creature with a pig-like snout lying on the bank of the Rio das Caveiras. The bizarre creature then proceeded to disappear into the ground while leaving a trench behind. Müller would go out to investigate these claims, and while he did not find the creature he sought he did come across unexplained trenches dug through the earth as if by some large serpentine animal of some kind.

The creature was sporadically sighted in later years as well, although accounts became exceedingly rarer until they dropped off altogether, and reports are nonexistent in more modern times. There have been several theories as to what these creatures could have been. Cryptozoologist Karl Shuker speculated that the Minhocão was perhaps some sort of undiscovered giant caecilian, which are limbless amphibians that look very much like earthworms and which are native to the regions where the cryptid was seen. Famed cryptozoologist Bernard Heuvelmans wrote in his masterpiece On the Track of Unknown Animals that the creature could perhaps be a surviving population of a giant prehistoric armadillo called the glyptodont. Then of course there is the idea that this could be something totally new altogether, but unfortunately there is no way to know, and with the lack of modern sightings there is the possibility that it does not exist anymore, that is if it ever even existed at all.

While the thought of giant, carnivorous underground worms is already quite disturbing enough, the idea of underground demon bats is probably just as bad. From the jungles of Cameroon, in West Africa, as well as from Republic of Congo, Zimbabwe, and Zambia, there have long been reports of giant bats with black skin, huge serrated teeth, and 12-foot wingspans, which are called the Olitiau, or more commonly known as “cave demons.” These mysterious gigantic bats are said to spew forth from underground caves at night to prowl the land in search of prey, which is basically anything they can catch.

By far the most well-known account of the Olitiau was given by the cryptozoologist Ivan T. Sanderson, who had his own encounter with one of the creatures while out in the field studying Hammer-headed fruit bats in southern Cameroon in 1932. Sanderson claimed that he was set upon by an enormous bat, which he estimated as being four times bigger than the fruit bats he was after and which he dubbed "the granddaddy of all bats.” It gave him quite a fright, and when he asked the local guides about it, they fearfully told him that it had been an Olitiau, that it had come from a nearby cave, and that it was best they get inside as there would surely be more not far behind.

A similar bat-like cave dweller was investigated on the TV show Underground Monsters, in which a team goes into an underground cavern complex in Flagstaff, Arizona, in the United States, seeking what they refer to as the “Volcano Cavern Olitiau.” The episode rather dramatically shows the team hearing unexplained noises within the caves and picking up anomalous heat signature readings down in the murk shortly before their night vision gives out, leaving them to panic. Just as questionable is an account covered on the TV series Lost Tapes, which features an account of underground bat-monsters in the caves of Tora Bora in Afghanistan, supposedly given by a unit of U.S. Marines who describe being attacked by a nest of humanoid bat creatures while exploring the area in 2002. Unfortunately, like many other cryptid-hunting shows the whole thing in both of these cases is played for maximum spooky effect and it is uncertain how much veracity any of it has.

Perhaps some of the scariest reports of subterranean monsters are those that are what can only be described as some sort of mysterious humanoid creatures that apparently dwell down in the gloom under our feet. One such report comes from a publication called the Chase Post in 2007, which printed an article that linked a rash of Bigfoot and "Werewolf" sightings in the area of Cannock Chase, England, to what they describe as “a tribe of subterranean creatures.” The newspaper went on to say:

The strangest rumor has come from a senior local resident who believes the mysterious intruders to be subterranean. He told us: ‘The creatures have made their way to the surface via old earthworks to hunt, for example, local deer.’

In another account of apparently ravenous underground creatures we have a very bizarre account from the July 14, 1974 edition of News Extra, which reads like something from a horror movie. According to the article, in 1944 a mining inspector’s report filed by an Inspector Glenn E. Barger claimed that 15 miners had been eaten alive by some sort of humanoid monster down in the dank mines of Dixonville, Pennsylvania after a mine cave-in. When rescuers arrived they found the horrific sight of mutilated bodies, as if by a fierce wild animal. It was enough to keep anyone from ever using the mine again, and apparently this was all kept under wraps for decades before being brought to light by Barger’s son, Frank.

According to the unsettling original report, Barger had been summoned by the mining company to find out what had happened to the vanished men. Together with another inspector named Ted Walters, the two penetrated down into the darkness and eventually found the bodies of the miners, who had been mauled by some sort of powerful creature. Barger would say of the first corpse they stumbled across in the gloom, “That man wasn’t killed by any cave-in. He must have been killed by some sort of animal; that was obvious.” They would find the rest of the bodies all in the same state of being savaged, with still others nowhere to be seen, and as horrifying as all of this was things got worse when the two rescuers also suffered a cave-in and got stuck there in the mine along with the dead bodies and whatever had killed them. As they waited for rescuers to come get them, Barger claimed to have taken a nap only to awaken to something there with them, which was described as some sort of shadowy humanoid beast. He would say:

I fell asleep for a time. It wasn’t long. Suddenly, I felt a hot breath on my face. That thing wasn’t of this world. We sat silently, reflecting on our fate. I swear, I expected some slimy thing to drag the both of us away.

He would later even speculate that whatever it was had intentionally caused the cave-in to trap them in there, and that it had probably done the same with the dead miners. In this case whatever it was ultimately decided to leave them alone to slink away into the blackness of the mines, and rescuers reportedly came through a few hours later. It is all a very harrowing account, but I have been unable to find any other corroborating source for it and one wonders whether it is a fanciful spooky story or if it has any veracity at all. As much as it stirs the imagination, one wonders if there is anything to this story.

There was another rather ominous account from McAlester, Oklahoma, which supposedly took place just before the Korean War. Three men purportedly went exploring in a cavern in the area beneath what was described as a “haunted mound,” where all manner of strange phenomena allegedly happened, including ghost lights, cattle mutilations, and missing people and livestock. The three unidentified men apparently pushed into the cavern to find a stone staircase that disappeared down into a “bottomless shaft,” which they descended down for around a mile with no bottom in sight.

The three explorers began to worry about whether they’d ever find their way back and headed back up the precarious stairway. They managed to make it up, at least two of them did, when they heard a scream from the third down below, followed by a gunshot. The third man soon came scrambling up out of the dark, white with fear and shaking. He explained to the others that as he had been coming up the stairway behind them, “hairy animal-men” had pounced upon him and attacked him. He showed them some yellowish liquid on his clothes that he claimed had come from one of the creatures he had shot, which was enough to send them all on their way out of there as fast as they could.

In our modern times there seems to be no end to our relentless push into the wilds of our planet. The places where mysterious creatures can hide are shrinking day by day in our insatiable drive to conquer our planet. However, one frontier seems to remain rather well-hidden from our eyes, and that is the domain of dark that meanders out beneath us. What secrets, curiosities, and wonders do these subterranean worlds hold? What creatures call them home? It is hard to know for sure, but when reading reports such as we have seen here it seems that there is still possibly much that remains hidden from us, and things that stalk about in the inky black where few of us dare to tread.

Brent Swancer

Brent Swancer is an author and crypto expert living in Japan. Biology, nature, and cryptozoology still remain Brent Swancer’s first intellectual loves. He's written articles for MU and Daily Grail and has been a guest on Coast to Coast AM and Binnal of America.

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