Treasures of the Deep: 7 Underwater Discoveries That Left Experts Amazed

Roughly 5% of our planet's ocean floor has been explored.


Even though humankind has managed to explore and map distant worlds like mars or even the Moon, only a small area of our planet’s oceans has been explored.

It’s perhaps because we are more interested in what’s in space, up there than what’s down there.


Humankind has looked since time immemorial towards the skies, looking for answers that only the stars can provide.

Little have we wondered about the many treasures that may lie hidden beneath the world’s oceans.

In fact, according to numbers, only 5% of our planet’s ocean floor has been explored.

This means that around 95% of the ocean remains unexplored.

This is kinda’ shocking since our oceans occupy as much as 70% of the planet’s total surface and 90% of the living space on Earth.

As explained by World Atlas, “the entire ocean floor has been mapped to a maximum resolution of approximately 5 km, meaning that all features on the bottom of the ocean floor larger than 5 kilometers across have been mapped.”


Weird Discoveries

And although we have not managed to explore our planet’s oceans fully, the little we did explore has yielded some incredible things.

From lost cities to strange objects, underwater explorers have recorded some of the strangest discoveries beneath the surface of our oceans.

Many things remain unexplored, and scientists estimate that many species exist in the ocean that we have never encountered before.

In fact, it has been theorized that the ocean floor is home to extensive valleys that are even deeper than the Grand Canyon.

Knowing this, you can’t help but wonder what mysteries remain undiscovered.

But let’s turn towards the discoveries that we have already made.

Lost City of Dwarka

This is when legends turn into reality.

The ” Lost City of Dwarka” has been dubbed the Atlantis of India.


Dwarka was the ancient city of Lord Krishna. This city was considered, until its discovery, one of the many mythical places throughout the world. However, when its ruins were discovered in 2,000, myths turned into reality.

The ruins of the underwater city lie at a depth of 121 feet beneath the ocean’s surface, in the bay of modern-day Dwarka, one of the oldest cities in India.

Studies performed on the site have shown an incredible geometric alignment of the structures once located above the surface.

Many ancient artifacts were discovered on the site, and some of them helped experts date the submerged city to 7,500 BC, although some experts disagree.

Looking back at history, the last time the sunken city’s area was above the surface was around 9,000 years ago.

The Antikythera Mechanism

The so-called Antikythera Mechanism is a sophisticated mechanical device discovered off the Greek Island of Antikythera in 1901.

Dating back at least 2,200 years, the device is thought to have been used in ancient times as an analog computer, facilitating astronomers to predict celestial events and cosmic positions.

The Antikythera mechanism (Fragment A – front); visible is the largest gear in the mechanism, approximately 14 centimeters (5.5 in) in diameter. Image Credit: Wikimedia Commons.
The Antikythera mechanism (Fragment A – front); visible is the largest gear in the mechanism, approximately 14 centimeters (5.5 in) in diameter. Image Credit: Wikimedia Commons.

Several tests have been performed on the mechanism, including X-Rays.

The research has shown that the Antikythera Mechanism is, in fact, a sophisticated system of interlocking gears.

It was so advanced that a similar device approaching its complexity and workmanship would not appear anywhere on the planet until the 14th century.

The underwater ruins of Yonaguni

Dubbed Japan’s Atlantis, the underwater complex of Yonaguni has given experts and scholars a lot to talk about.

The site is one of the greatest aquatic mysteries on the planet.

Discovered by diver Kihachiro Aratake in 1985, the underwater complex has attracted numerous tourists and scholars eager to explore the site.

The Yonaguni complex resembles a massive submerged pyramid.

Some experts argue that the now submerged structure is evidence of complex civilizations inhabiting our planet before the last ice age.


Others say its just an intricate natural formation that looks a lot like a human-made structure.

Lost City of Heracleion

Many cities have tested our understanding of myths.

Like Atlantis, the city of Thonis-Heracleion was considered one that existed only in myths.

However, in 1999, the French archaeologist Franck Goddio came across a forgotten city’s sunken remains lost to the ocean.

The city of Heracleion was a port city in Pharaonic, Egypt, and was of extreme importance to the kingdom. In fact, it was in the temple of this city where new Pharaohs received the divine power of Amun that eventually legitimized their reign over the lands.

But despite its riches and importance, the city was no match when mother nature decided to strike.

A Mythical ship described 2,500 years ago

The Greek historian Herodotus wrote about a mysterious boat from the ancient world in Egypt some 2,500 years ago.

The ship was considered a myth as never had the ship’s remains been found by experts exploring Egypt.

Known as a baris, the Greek writer described seeing it sail around 450 BC when he traveled across Egypt.

A shipwreck at the sunken port city of Thonis-Heracleion. Image Credit:

When experts discovered the sunken city of Heracleion in 1999, they came across dozens of shipwrecks.

Among them was one that stood out from the rest.

Later studies showed that the shipwreck found at the bottom of the sea was the one Herodotus described in his writings, proving that the boat was not a myth and existed in ancient times.

Sunken Pirate City

Mother Nature devoured a Pirate City at Port Royal in 1692.

Shocked eyewitnesses watched as a devastating earthquake caused an entire city to sink.

Port Royal, known in antiquity for being a privateer and Pirate City, was eventually swallowed by the ocean.

The remnants of the sunken city.

Built on the southeastern coast of modern-day Jamaica, the city of Port Royal became one of the most famous Caribbean cities in history, and at the time, one of the largest European cities in the New Continent.

According to reports, the city sank after a 7.5 magnitude earthquake struck the island. Since the city was mostly built above the sand, the cities weight crumbled beneath the surface, causing nearly 35 acres of the city to sink.

The earth opened and swallowed many people before my face, and the sea I saw came mounting in over the wall, upon which I concluded it impossible to escape.”

Cleopatra’s Sunken Palace

Some 1,400 years ago, a powerful Earthquake struck Egypt. It unleashed a tsunami that would eventually impact the coast of Alexandria.

The rising water missed nothing. Before reaching the port city of Alexandria, the natural disaster caused the island of Anithodos to sink.

The island, located on the Eastern Harbor of Alexandria, sank together with Cleopatra’s palace. Franck Goddio rediscovered the site in 1996.

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Written by Ivan Petricevic

I've been writing passionately about ancient civilizations, history, alien life, and various other subjects for more than eight years. You may have seen me appear on Discovery Channel's What On Earth series, History Channel's Ancient Aliens, and Gaia's Ancient Civilizations among others.

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