How much do we really know about the deepest parts of the sea? Today, in the era of super advanced technology, one might think that we know everything there is to know about every little corner of the Earth. Unfortunately, that is not entirely true. Even though water covers over 70% of our planet’s surface and the ocean floor has been fully mapped, there are parts deep down that still remain a mystery. One of the reasons behind that is that it is impossible (for now) to send humans to research the deepest parts of the ocean simply because they wouldn’t survive the pressure of the water. So we had to find effective alternatives like, for example, satellite images.

Although we don’t know everything about the darkest places deep beneath the water’s surface, the things that we do know are fascinating and sometimes even downright terrifying. People have discovered amazing creatures that have evolved to survive the most extreme living conditions imaginable. They have discovered unbelievable items that were made by humans before they were lost to the sea. Still, so much still remains undiscovered and so many parts of the big, wide water remain mysterious. If you’d like to learn more, here are 15 creepiest things discovered in the deepest parts of the sea.

15. “Crop Circles” on the Bottom of the Sea

We’ve all heard of crop circles – the mysterious patterns created in the middle of fields by who knows who. There also have been movies about this phenomenon, suggesting that crop circles were made by aliens. However, scientists agree that there is no reason to believe that, because the patterns are consistent with human causation. But when you find something resembling crop circles at the bottom of the sea, that is a completely different story. They were discovered by Yuji Ookata and they left him really puzzled. However, today we know the story behind this phenomenon. Those patterns are created by the male Japanese puffer fish in order to attract females. If the female fish “likes” the pattern, she will lay her eggs there for the male to fertilize.

14. Gigantic Eye

This huge eye was found in the sea, just floating around, with the rest of the body nowhere to be found. We have no idea who the eye belonged to and it reminds us of how little we really know about the secrets hidden in the deepest parts of the sea. What we do know is that the eye is so big that a person needs to use both hands to carry it. We know that the owner must have been gigantic, maybe some kind of a whale or maybe some unknown huge monster, hidden somewhere deep below the surface. We can’t tell for sure, but it is definitely creepy to think about something like this floating around while you’re swimming, with the owner’s cousins swimming somewhere underneath you.

13. The Ice Finger of Death

When this curious picture was captured deep down in the waters of the Antarctic, scientists weren’t really sure what the strange phenomenon in the picture actually was. It is called The Ice Finger of Death, but it’s not as scary as the name might sound. It is actually a brinicle: kind of like an icicle, but with the salty components called the brine. It looks a little bit like a pipe of ice with extremely cold saline water inside. So why do we call it the Ice Finger of Death? Well, the truth is, it can be pretty dangerous to the sea life around it, simply because it is a lot colder than the surrounding water. It can trap and freeze little creatures, such as urchins or starfish, causing them to die.

12. Loki’s Castle

Loki’s Castle is an area with active hydrothermal vents discovered in 2008 by members of a scientific expedition from Norway. It is located in the Atlantic Ocean, between Greenland and Norway. There are five active chimneys venting 300°C hot water that makes it impossible for most sea life to live in the area. However, scientists have discovered a specific type of microorganism and vent fauna that have evolved to survive such high temperatures. The name Loki’s Castle really makes sense when you think about it. Loki is the ancient Nordic God of fire and trickery and the whole thing really looks like some kind of a magic castle where such a god would live. Of course, it is really hot, and it was also very tricky to find. Sounds like a perfect place for Loki.

11. Goblin Shark

If there was a contest for the creepiest and ugliest deep-sea fish, this guy would probably be the winner. It is a very rare species of deep-sea shark that’s around 125 million years old. It is also a living fossil because it has no other relatives alive. It lives at depths greater than 100m in all three major oceans, but it poses no threat to people because it lives in the deep corners of the sea and it was also proved to be very inactive. It has also almost no commercial value, so it is not targeted by fishermen. People simply let it live in peace in its deep parts of the sea. The captures that did occur in the past were always isolated incidents.

10. Underwater Cities

There have been numerous underwater cities discovered around the globe. The famous legend of Atlantis is something everybody has heard about. It is a tale of a lost city that was submerged by the ocean. People have been looking for this city for decades, but Atlantis still remains lost. However, other unbelievable cities have been discovered and researched. There is a town called Port Royal in Jamaica that was destroyed by an earthquake in 1962, then there are the amazing pyramids of Yonaguni-Jima in Japan. There is also a beautiful city in the Gulf of Cambay, India, that is believed to be the lost city of the lord Krishna. Who knows what cities are yet to be found in the deep parts of the huge dark water around the globe?

9. Vampire Squid

While this squid might look just like any other squid (and they’re all pretty creepy), this one is actually a squid from Hell! Well, not really, but its name “Vampyroteuthisinfernalis” suggests so since, it literarily means “Vampire Squid from Hell.” Poor little guy! It must be hard to live with such a horrible reputation deep down in the sea. The vampire squid is a living fossil, which means it has no other living members in its order. It is about 30 centimeters long and it has crimson colored skin, which looks a little bit like a cloak. This is part of the reason why it’s called a vampire squid. It is definitely not something you would like to come across while swimming in the sea. Fortunately, it lives deep enough for you to never encounter it.

8. Frilled Shark

As if regular sharks weren’t scary enough, here is the shark’s even creepier cousin – the frilled shark. In truth, it’s not really the shark’s cousin because all of the frilled sharks’ closest relatives have been extinct for a long time, making it a living fossil. Actually, the only thing that sharks and frilled sharks have in common is their name. Oh yeah, and you probably wouldn’t want to meet either one of them in the middle of the sea. However, you don’t need to worry too much about this one because it has only been spotted a couple of times. Some even think it has gone extinct, but we don’t know that for sure. What we do know is that the frilled shark is about 2 meters long, it swallows its prey whole like a snake, and it lives (or used to live) in the deepest parts of the Atlantic and Pacific Oceans.

7. The Baltic Sea Anomaly

One day, a Swedish diving team called Ocean X discovered something suspicious and unexplainable in the Baltic Sea. They had no idea what it was, so they took a sonar picture. The picture was later published, and it caused crazy speculation worldwide. What we saw in the picture was an unusual rock formation that looked very much like the spaceship Millennium Falcon from the Star Wars movies. Of course, tabloid newspapers immediately saw the potential for a bombastic story and from that moment on, everybody was talking about the UFO found at the bottom of the sea. Unfortunately, we don’t know for sure what it is because full research was never conducted in order to determine the origin of this peculiar formation. However, most scientists agree that it is probably just a natural undersea formation and that there was a lot of fuss for nothing.

6. RMS Titanic

This case wasn’t really very mysterious, but it was still quite horrible. The shipwreck of RMS Titanic – the unsinkable ship – was found about 350 miles Southeast of Newfoundland. There have been numerous unsuccessful expeditions that failed to locate the wreck. The reason was the combination of bad weather, inadequate technology, and inaccurate position given in Titanic’s distress signals. It was finally discovered by Robert Ballard on September 1, 1985, 73 years after its descent. People around the world saw the picture of the shipwreck in their newspapers the very next day and it seemed like the whole world was talking about Titanic at that moment. It became even more popular after James Cameron’s 1997 movie Titanic was released. There has also been some talk of opening the shipwreck site for tourists in 2018.

5. Pacific Viperfish

There are many creepy creatures hidden in the darkest corners of the sea and the Pacific Viperfish is one of them. This guy looks like something out of a horror movie. While he lives in the deepest parts of the sea, as deep as 5000m below the surface, during the day, he swims into shallower depths (200m or less below the ocean surface) in search of food. He is usually up to 1 foot long and attracts smaller fish with his photophores, then he kills his prey with his long and sharp fang-like teeth. When you look at this photo, you can understand why it’s called a viperfish. That large mouth and the needle-like teeth really make its head look like the head of a viper. Just stay deep down, little guy.

4. Giant Squid

People have been talking about the giant squid for decades, but it was thought of as nothing more than a legend, sort of like the story of the Loch Ness monster. Well, it’s not just a legend anymore, since it was actually captured by scientists in 2006. As the name suggests, it really is one deep-sea giant. Male squids can grow up to 13m in length, while females can grow up to 10m. There has been some speculation about different giant squid species, but for now, only one has been confirmed – genus Architeuthis. It feeds on deep-sea fish or smaller squid species, but it was also proved to be cannibalistic. The fully grown giant squid has only one known predator, the sperm whale, while the younger, smaller squids are also attacked by deep-sea sharks.

3. Underwater Pyramid in Azores

Something interesting was discovered under water between the islands of Sao Miguel and Terceira, in the Azores. It appears to be a 20,000 year old underwater pyramid. It is 60 meters high and the base is 8,000 square meters large. We don’t know its origins and we’re not even sure if it was made by humans or if it is yet another interesting natural formation. The weird thing about it is the fact that it was discovered so late, in 2012, even though people have been studying volcanic activity in that area very thoroughly for quite some time. So the big question, which was a reason behind many new conspiracy theories being created, is why the existence of the pyramid wasn’t reported earlier. People believe that, for some reason, people have been hiding what they found.

2. Coelacanth

Discovering this fish was extraordinary because it was believed to have been extinct since the Cretaceous period millions and millions of years ago. On December 23, 1938, museum curator Marjorie Courtenay-Latimer found the first specimen of the coelacanth in a local angler’s fishing net. The fish has no real commercial value, but the thing that makes it special is that it was considered extinct for 66 million years and it is still the most endangered order of animals on the Earth because there are only 2 types. They are related to lungfish, reptiles, and mammals because they follow the lineage of Sarcopterygii. They can be found in the Indian Ocean. You can really never know what the sea will wash up that was previously hidden deep down.

1. Big Red Jellyfish

Tiburoniagranrojo, also known as the big red jellyfish that was originally called “Big Ugly”, is one of the largest jellyfish species and it lives up to 1,500 meters below the ocean surface. It was discovered in 2003 by Dr. Matsumuto and the discovery was announced in Marine Biology. They have been found in a couple of different parts of the Pacific Ocean, such as Monterey Bay and the Gulf of California. Their body is entirely red and can grow up to 76 centimeters. They don’t have tentacles like most of the other jellyfish species, but they have fleshy oral arms instead. They are actually quite hard to find. So far, only 23 of them have been spotted, and only one was caught for the purpose of further study.