We all know the ocean is huge, it covers 70% of the Earth’s surface, after all, but how deep is it? Let's go on a deep dive, journeying from the majestic surface of the water down through each and every inhospitable layer into the ocean’s deepest, darkest, eeriest trenches to discover just how deep the ocean really is.

Epipelagic Zone

0-650 Feet (0-250m)

We begin our journey above the waves, at sea level. Plunging into the water itself we enter the Epipelagic zone, which is sometimes also called the daylight zone due to the amount of sunlight penetrating the water.

Of course, lots of sunlight means lots of green! Around 130 feet beneath the surface we start seeing huge kelp forests. Underwater seaweed and kelp jungles don’t just provide food and shelter for all sorts of marine life, but they’re also responsible for 70% of all the oxygen on Earth!

Venturing just 20 feet deeper, we reach the perfect environment for coral to thrive. While corals may look like rocky vegetation, they’re actually a type of animal, closely related to jellyfish. An estimated half a trillion corals worldwide create colorful reefs that many shallow-dwelling fish call home, such as the clownfish and butterflyfish.

The shallowness of these waters can make them dangerous, however; diving predators like birds, seals, and even polar bears can reach here, so many fish only swim here to feed before venturing into deeper waters. Fish like tuna, herring, and mackerel tend to spend a lot of time in the epipelagic, coincidentally, these are all fish we tend to eat.

At around 200 feet down we meet the King Crab. These little pinchers live at the perfect depth to be scooped up not only by humans, but also halibut, octopuses, and even sea otters. Sinking to around 260 feet, we may spot the velvet swimming crab, unusual little crustaceans that flap their appendages in order to swim underwater. Despite this extra mobility, these little guys stick within a few hundred feet of their homes.

300 feet beneath the surface lies the wreckage of the HMS Britannic. This was the Titanic’s sister ship, which sank four miles off the coast of the isle of Kea in 1916, just three years after the Titanic. Guess sinking runs in the family. Of the two, the Britannic is by far the better-preserved wreck, with the 53,200-ton ship lasting over 100 years. It’s also shallow enough to visit, if you scuba! In fact, many shipwrecks never make it past the epipelagic Zone, often getting caught on rocks or resting on shallow sea beds.

At 450 feet down, we reach the average depth of a sea lion dive, though they can plummet as low as 900 feet down. Still, this average dive is about as deep as the Great Pyramids are tall!

A little over 500 feet down we reach the favored depth of the iconic green sea turtle. These majestic creatures call the lower levels of the Epipelagic their home, though like many sea creatures, they can dive much deeper if they feel like it.

If they do, they may pass the unusual Oarfish, which lives around 600 feet down. These legendary silvery fish have long, flat, snakelike bodies and they can reach quite impressive lengths, the longest on record being 36 feet from head to tail. Like many large ocean creatures, however, they live off krill and plankton, and dwell at depths as deep as the Space Needle is tall!

Mesopelagic Zone

650-3,300 Feet (250-1000m)

We’re now moving onto much greater fathoms, as we move into the Mesopelagic Zone, also known as the Twilight Zone. This area of the ocean extends from 650 to 3300 feet below sea level, and earned its nickname due to the fact that it slowly transitions from bright to dim waters, becoming dramatically darker the deeper we plunge. The Mesopelagic is also the liveliest area of the ocean. Nearly 90% of marine life, measured by weight, at least, call this area home.

And of course, one of it’s first denizens we’re going to meet is the Great White Shark. These apex predators usually lurk around 650 feet beneath the surface, can swim up to 25 miles per hour, and can smell a bleeding creature from three miles away. If they want to, they can migrate as deep as 3900 feet beneath the surface, just in case you thought it was safer to go deeper, for some reason.

At 831 ft, we pass the deepest point a human free diver has reached. This record, set by Herbert Nitsch, was achieved without any oxygen tanks, and so required the use of a ground breaking torpedo apparatus to quickly deliver him to that depth.

This gave him enough time to make it back to the surface, still holding his breath, while battling against 25 atmospheres of pressure. At this depth, the pressure particularly affects any cavities in the body, such as lungs, eardrums and sinuses. 980 feet down we reach the maximum dive of the common dolphin, though as we’ll discover, other cetaceans can dive much, much lower.

At 1089 feet beneath the surface, which is deeper than the Eiffel tower is tall, we arrive at the deepest point a human has reached while diving. This was accomplished in 2014 by Ahmed Gabr, who managed this with the help of a team of support divers, resupplying him with oxygen every few hundred feet. This was because Gabr could not reliably carry the multiple oxygen tanks necessary for the round trip.

Another human milestone was reached at 1300 feet; the depth of the very first bathysphere plunge. Designed back in 1930, this bathysphere was a 4,500-pound hollow steel ball, some 5 feet in diameter, which was raised and lowered from a ship by a cable. It was designed by zoologist William Beede and engineer Otis Barton, and while cramped and difficult to operate, the two men journeyed deeper than any humans had ever travelled before.

1453 feet down, we’re at a depth equal to the height of the Empire State Building. As we move deeper into the ocean, light energy is scattered and absorbed by water molecules, meaning it gets darker the deeper you descend. Creatures past here tend to develop larger and larger eyes, like the Bigeye Tuna. These eyes are designed to soak up as much of the sparse light as possible in the murky depths.

1850 feet beneath the surface, we meet an unexpected visitor; the Emperor Penguin. Shockingly, these birds often dive this deep looking for fish. Far more graceful in the water than on the surface, these birds can swim as fast as 8.9 miles per hour, over five times their land speed. This means the birds can dive deeper much quicker, reaching depths that are greater than the height of any of the buildings in the New York skyline.

At 1950 feet down, we meet a strange creature. The Sunfish, as it’s known, can grow to be 10 feet long, 13 feet tall from fin-to-fin, and weigh as much as 5000 pounds. However, they lack an air bladder, which is the organ that allows many fish to rise vertically in the water. The sunfishes’ poor control, massive body, and general helplessness has led some mean marine biologists to debate how they even evolved to this point! Talk about a freak of nature.

Around 2000 feet down we meet the spider crab, and it’s one creepy crustacean. Though the Japanese spider crab’s carapace is only 12 inches, its total legspan can reach a gargantuan 12 feet. To survive the near 61 atmospheres of pressure at this depth, which is about the same as having 115 elephants standing on top of it, the crabs organs are protected by an incredibly tough shell, with almost no air cavities in their internal structure. So, compared to their tiny cousins in the shallows, these crabs are more monstrous inside and out.

As we continue down to 2300 feet, we move from spiders to slugs. Unlike terrestrial slugs, sea slugs are actually quite beautiful, and come in a variety of mesmerizing colors and patterns. It’s thought that sea slugs, or nudibranchs, evolved to be bright and garish as a defense mechanism. At this depth standing out is scary. Most predators think if something isn’t trying to hide, it must be because it’s dangerous or toxic.

3000 feet down, we reach the lower domain of the monkfish. These unusual, flat predators lie motionless on the ocean floor, waiting to pounce on prey attracted to their dangling antennas. Animals as diverse as ducks and even sea otters have been found in the bellies of these gluttonous creatures. Despite their pretty ugly appearance and ability to live fairly deep in the ocean, their sweet and firm meat is considered good eating throughout Europe and Asia.

At this point, we’re at a level deeper than the Burj Khalifa is tall, and that’s the tallest building in the world! While it may be hard to believe, we’re still a long way from the bottom. In fact, even the average depth of the ocean might surprise you.

Lurking beneath that inverted skyscraper at around 3300 feet below sea level, swims the mysterious Colossal Squid. These legendary leviathans can weigh up to 1200 pounds, with the longest on record measuring in at a whopping 46 feet. Even today, shockingly few of these creatures have been observed alive, with most of our knowledge of them coming from dissected corpses.

The Colossal Squid perfectly represents the phenomenon of deep sea gigantism, the tendency for marine invertebrates to grow ever larger the deeper down you go. Why this happens is something of a mystery, but researchers have suggested that due to lower temperatures at these deaths, which rarely reach more than 4°F, an organism’s metabolism is much slower, allowing them to live longer and grow larger. The Humboldt squid, which lives 1000 feet higher than the colossal, measures in a little under five feet long, while common squid closer to the surface are often less than a foot long.

Bathypelagic Zone

3,300-13,000 Feet (1000-4000m)

Now we reach the eerie Bathypelagic Zone, also known as the midnight zone. Almost no sunlight reaches these depths, which spans from 3300 to around 13,000 feet beneath the surface. To survive in the pitch black, many creatures in these depths are bioluminescent, meaning they produce their own light sources organically, such as the nightmarish deep-sea anglerfish.

Found at some 3450 feet beneath the surface, these terrifyingly toothy fish use the bioluminous lures atop their heads to attract unsuspecting prey. Once the smaller fish get close enough, they’re ripped to shreds by those awful mouths.

They also exhibit some of the strangest breeding habits in the animal kingdom. While females can grow up to five feet long, males are usually about the size of houseflies. In order to mate, the males bite and latch onto the females, then slowly dissolve into them, fertilizing their eggs in the process. Really sets the tone for how much gnarlier things are in the deep, doesn’t it?

3,800 feet, and about 115 atmospheres beneath the waves, we encounter the one and only meme-king; the blobfish. More accurately called the Psychrolutes marcidus, you probably know the blobfish from this very unfortunate image, which makes it look like the most pathetic creature on earth.

However, to defend the poor blob, you should know that the famous image was taken after it was brought to the surface. Like many deep sea fish, the blobfishes’ body resists pressure through compounds called trimethylamine N-oxide, or TMAO for short. This chemical forms strong bonds with water molecules, allowing skin and organs to resist pressure.

The blobfish is designed to thrive in waters exerting over 100 atmospheres of pressure. Like the sunfish, the blobfish doesn’t have an air bladder, so it really isn’t meant to live very high up, as its soft body simply deflates above the water.

Translucency becomes more common in sealife as we venture deeper into the ocean, due to the lack of sunlight, which reduces melanin production in the body. Melanin is one of the compounds used by both fish and mammals alike to produce pigmentation in the skin.

Translucency is also a useful adaptation, however, when avoiding predators. An interesting exception to this is creatures with red coloration. This occurs because red is the first color to leave the visible spectrum at these depths, meaning down here, a totally red creature is almost as good as an invisible one.

A great example of this is the Big Red Jellyfish, which lives approximately 4,800 feet down. This bulbous blob can grow to over 3 feet in diameter, but for all its size, it’s red color makes it difficult for predators to spot in these murky depths.

Deep relaxation: Breathe deep with the big, red jellyfish Tiburonia granrojo by MBARI (Monterey Bay Aquarium Research Institute)

5,200 feet down, however, the opposite is true. Here swims the charming glass squid. whose body is almost completely see-through. The skin of the glass squid, along with most cephalopods, is covered in tiny pigmentation sacks called chromatophores. By keeping these sacks closed, the little squid becomes ghostly and translucent. They even produce very faint light around certain areas of their body, like the eyes, to mask shadows!

Glass squid use an invisibility cloak to stay safe in the twilight zone by MBARI (Monterey Bay Aquarium Research Institute)

Plummeting down to around 5,700 feet, we pass the migratory sixgill shark heading in the opposite direction. These sharks are unique in that they have a pretty strict routine; during the daytime, they can be found in the bathypelagic zone. At night, however, they drift upwards to hunt in waters as shallow as 300 feet.

It’s theorized the sharks do this because they prefer colder temperatures; so, as the sun goes down and the shallows cool, they migrate there to hunt. When those waters begin to warm up, they sink back down into the depths, where they digest and conserve energy. They’re more disciplined than most of us!

Approximately 6,000 feet down, brilliant displays of color still float through the dark. This miraculous creature is the Halitrephes Maasi, dubbed the firework jellyfish due to its spectacular bioluminescence.

A Burst of Deep Sea Fireworks: Halitrephes Jelly | Nautilus Live by EVNautilus

Little is known about this mysterious creature, which stands in stark contrast to common jellies found in shallower waters. What we do know is that it’s never been seen above 4000 feet. Still, this enigmatic creature is a cool reminder that even bizarre creatures like jellyfish can become more alien the deeper we go.

7,000 feet beneath the surface is where we find the majority of the planet’s hydrothermal vents; underwater fissures in the Earth that spew out natural gases and warm the water around them. Some hydrothermal vents can get as hot as 700°F, which is extremely dangerous to most marine life. Still, certain bizarre creatures like the Yeti Crab aren’t afraid of them at all.

These unusual crustaceans have bodies covered in a thick layer of fuzz. By hanging out near hydrothermal vents, they’re able to farm their own food, eating the bacteria that thrive in warmer waters and cling to their bodies.

Yeti Crabs from Hydrothermal Vents in Southern Ocean 1 by Craig McClain

Around 8,000 feet down we meet a truly unique character; the Barreleye fish. Remarkably, this creature has an opaque body, but a translucent head. The bright green eyes in the center of the fishes head can swivel around completely, meaning the fish can peer through its own head when on the lookout for food and predators. It’s eyes and brain are protected by a transparent fluid, but as you can imagine, that still makes the freaky fish fairly fragile.

Entering a particularly spooky section of the ocean, we meet a trio of creepy deep-sea dwellers. 8,500 feet down swims the ghoulish chimaera, also known as the ghost shark. The unnerving creature wasn’t discovered until 2002, even though estimates suggest that they’ve existed for over 360 million years. Despite the moniker, the ghost shark isn’t actually a shark; in fact, their teeth aren’t even sharp. Instead, they have blunted plates better suited to crushing their meals than shredding them.

At 9,000 feet we encounter the terrifying gulper eel. While they initially appear tiny, these predators silently sneak up on unsuspecting prey in the dark before unhinging their enormous, elastic jaws and swallowing them whole.

Disturbingly, the eel is able to swallow creatures larger than itself. When it does, the prey is deposited into a second bulbous, protruding jaw, which acts as a kind of horrible cage the creature is stored in until digestion.

Gulper Eel Balloons Its Massive Jaws | Nautilus Live by EVNautilus

9,500 feet down we meet the final member of our frightful trio; the awesomely-named Vampire Squid. This cephalopod has remained virtually unchanged for over 300 million years. On the tip of each of its deep red tentacles is an organ that produces a pale blue light, making it quite the striking animal.

It was recently discovered the vampire squid primarily feeds on something called ocean snow, though it’s not quite as whimsical as the name suggests. Ocean snow is the name given to dead organic tissue that drifts from the upper waters down into these depths, meaning the vampire squid likely scavengers on the remains of creatures it has never even seen.

9,800 feet beneath the surface of the waves, we reach the deepest point most mammals can dive, like the beaked whale.

Cuvier Beaked Whale off Kona, Hawaii by Lisa Denning -Ocean Eyes

While the beaked whale spends most of its time in pelagic waters slightly below 1000 feet, it can launch itself down nearly two miles, and has been known to remain underwater for as long as 222 minutes. It’s believed it can accomplish this through anaerobic respiration, which is a way of spending energy that doesn’t rely on oxygen.

At 10,000 feet, we reach the maximum depth of a sperm whale’s dive. These beautiful colossi can hold their breath for upwards of 45 minutes and swim up to 28 miles per hour. Consider the fact that these creatures can weigh up to 88 tons, but can still go from these depths, three times the length of the Empire State Building, to breaching the surface in a matter of minutes. How?

Their bodies are more flexible, with their ribs bound by loose, bendable cartilage, which allows the rib cage to collapse at pressures that would easily snap a human’s bones! These whale’s lungs can also collapse safely under pressure keeping them from rupturing, allowing them to hunt squid that thrive at these depths.

Let’s shoot all the way down to 12,099 feet. If you can believe it, we’ve only just reached the average depth of the ocean! For context, this is as deep as the entire Hollywood Walk of Fame straight down. Crazy to think we’ve only just reached the average depth, isn’t it? We haven’t even reached the trenches yet.

Finally, near the bottom of the Bathypelagic zone at 12,500 feet below sea level, we reach the wreck of the Titanic, undisturbed for over 110 years.

This behemoth of a ship weighed 52,310 tons, and was deemed unsinkable by its makers, White Star Line. As we all know, however, that sadly wasn’t true. On the 14th of April 1912, the Titanic struck and iceberg and sank, and it plummeted all the way down to these icy depths.

Of the 2240 passengers on board, only 706 survived. Very few of those that perished, however, would have made it all the way to the ship’s final, lonely resting place, as the natural buoyancy of the human body is much greater than that of 52,000 tons of metal. And if you can believe it, we still have much, much deeper to go.

Abyssopelagic Zone

13,000-18,686 Feet (4000-5700m)

Beyond even the resting Titanic, we sink deeper still. Starting at 13,124 feet, almost three miles down, we reach the Abyssopelagic Zone. Imagine the entire Daytona International Speedway laid out strait and heading straight down, and you have an idea of where these waters begin.

Journeying through the Abyssopelagic, you would not only experience over 400 atmospheres of pressure, but also freezing cold waters, and absolutely no light whatsoever. However, despite these near unlivable conditions, life still finds a way.

You might imagine that the creatures living in these waters are hideous monsters, but our first visitor is actually pretty cute. Somewhere around 14,000 feet down, we meet the adorable Dumbo octopus. These creatures are named for the two fins near the top of their head, which they can flap in order to aide their swimming, not unlike how Dumbo the elephant flaps his ears to fly. They need the extra mobility, too, Dumbo Octopuses lack the ink sacs of many other octopodes.

This is because the reason most creatures make ink is to obscure themselves as they flee from predators, and the abyssopelagic is already so dark that ink wouldn’t help. 15,000 feet down, the whimsical Sea Pig flutters on by. These strange, worm-like creatures almost defy categorization.

Though they’re technically sea cucumbers, they’ve evolved the ability to flap each end of their wiggly bodies to soar through the water. And don’t try to eat one, despite the name, sea cucumbers are simple marine animals, not vegetables for pickling. Even if you wanted to, these ethereal creatures are so fragile, without the pressure they’ve adapted to down here they literally disintegrate if brought to the surface.

Around 16,000 feet down lives the wacky Tripod fish. This little fish has three long, stilt-like fins it can rest against the ocean floor. This means the Tripod fish is not only one of the only fish able to stand, but it’s one of the few creatures on Earth you could argue is tripedal, meaning it has three legs.

Tripod Fish in Predation Stance | Nautilus Live by EVNautilus

These stilts can grow up to three feet long, impressive considering the little fish is only about 12 inches long itself. It’s thought it rests on these legs to conserve energy; Near the seafloor, the current is non-existent, but a few feet off the ground, the fish is perfectly positioned for tiny prawns and other sea life to be dragged by the current right into its mouth. Respect to this lazy fish!

You may have noticed that the stops on our tour are getting further and further apart. This goes to show how sparse life truly is in these depths, and how extraordinary the few creatures the live down here are. Still, the Abyssopelagic isn’t even the final region of the ocean we’re visiting.

Hadal Zone

18,686-35,839 Feet (5700-10924m)

Up next is the Hadal Zone, named after the ruler of the Greek underworld, Hades. It begins 18,686 feet beneath the waves, and is mostly made up of deep-sea trenches. The creatures that live in these depths tend to be simple, like chiton, a small mollusk that lives on rocks.

An exception to this, found 23,600 feet down, are the miraculous Comb Jellies. The creatures look more like alien spacecrafts than living animals, and despite their name, they aren’t jellyfish. They’re a unique species that has remained unchanged for almost 500 million years, which is probably what happens when you’re stuck in the dark.

A pretty pink color offers clever camouflage for the abyssal comb jelly by MBARI (Monterey Bay Aquarium Research Institute)

24,941 feet down, we find the mouth of the Mariana Trench. This is the entrance to the deepest chasm in the ocean, and it’s where explorers Don Walsh and Jacques Piccard found themselves on January 23rd, 1960. Like us, the men wanted to know how deep the ocean truly was, so put together a research team and created their bathysphere, the Trieste. The Trieste was around 50 feet long and 11 feet wide, however the two men needed to remain in a tiny pressure sphere throughout their plunge.

The two men journeyed down past the epipelagic, past the mesopelagic, past the bathypelagic into the abyss, and finally, down into the black chasm. 12 people in history have walked on the moon, but even today, only three have ventured down to the very deepest point of the seabed, known as The Challenger Deep.

At 29,040 feet the men were deeper than Mount Everest is tall. Then at 32,000 feet, a window cracked under the 969 atmospheres of pressure. Knowing it was too late to go back, the men continued down. After 4 hours and 47 minutes, they did it.

At 35,839 feet, some 6.7 miles down, and 1086 atmospheres of pressure, the Trieste settled at the bottom of the Challenger Deep. They achieved this only 30 years after the invention of the first bathysphere in 1929. Humans wouldn’t return here for another 52 years.

Throughout this article, we’ve used buildings, motorways, and mountains to contextualize the depth of the ocean. At 35,839 feet, however, there’s now nothing to compare it to. So, how deep is the ocean? Well, there’s nothing deeper.

If you were amazed at how deep the ocean is, you might want to take bring its depths straight into your home with our deep sea poster! You can purchase it here.