The history of our planet is full of incredible mysteries. The more we search and research, the more mysteries we uncover. And despite the fact that archaeologists and scientists work hard to figure everything out, we know very little about our past.

As Best Selling author Graham Hancock has said, we are a species with amnesia.

Proof of this is the countless discoveries that have been made throughout the years, which question our beliefs, the4 fundaments of society, and the capabilities of ancient civilizations.

Here, in this article, we bring you some of the most inexplicable, and history-challenging discoveries that have been made on Earth.

Sacsayhuamán

Sacsayhuamán is without a doubt one of the most incredible ancient sites ever discovered on the planet. Why? Not only because of the history of this ancient city but because of the supermassive stones used in its construction.

The ceremonial complex is well-known for its impeccable masonry that is so precise that engineers today have no clue how it was made.

Some of the stones at Sacsayhuamán are so perfectly fitted that not a single sheet of paper can fit in between.

The Gate of The Sun ( Puerta del Sol)

The Gate of the Sun is a megalithic solid stone arch or gateway located in Tiwanaku, an ancient mysterious city located in Bolivia.

Archaeologists believe this ancient city was the center of a vast empire during the first millennium AD.

And despite the fact that we know a lot about South American ancient civilizations, researchers are still not able to figure out the meaning of some of the drawings that are enshrined in the monuments of the ancient city.

Some experts believe these depictions have a great astrological and astronomical value, while other authors believe it is a gateway to another world.

The Longyou Caves

The Longyou Caves are out of this world. This incredible set of caves is little talked about.

The Longyou Caves are a set of artificial caves that are believed to be at least 2000 years old and happen to be one of the largest structures ever excavated by man.

Researchers have been baffled by the size and precision of the caves.

Archaeologists, engineers, architects, and geologists from around the world have tried to figure out how, why and when were these artificial caves were built, but no one has offered a single solution to the many mysteries surrounding the caves.

The underwater city of Yonaguni – Japan

Referred to as Japans Atlantis, some authors argue the Yonaguni complex is an ancient monument left behind by an ancient civilization that existed on Earth before the last Ice Age.

These alleged ancient remains were discovered accidentally by scuba instructor Khachiro Arataki.

Some underwater archaeologists, as well as many authors, refer to this ancient complex as one of the most important underwater discoveries in recent years.

The discovery of the Yonaguni complex has questioned several scientific theories.

The incredibly carved rock sank is believed to have sunken more than 12,000 years ago, much before the Ancient Egyptians built the Pyramids.

Mainstream archaeology and science argue that no advanced civilizations existed on Earth before the last Ice Age and that ancient mankind was not able to carve such a complex structure.

Mohenjo-Daro

The archaeological site of Mohenjo Daro is considered by many ancient astronaut theorists as one of the best examples of ancient alien contact.

The destruction of this once great city has been a mystery for archaeologists and experts for decades.

Ancient Astronaut theorists claim that thousands of years ago, advanced alien civilizations visited Earth, and nuclear bombs were used to destroy this city.

The city was discovered in 1992 when Indian archaeologist R. Banardzhi found the ancient ruins on the banks of the Indus River.

Questions such as the cause of the destruction and the fate of its inhabitants remain a mystery to scholars.

Some researchers have postulated theories that this city was destroyed by the gods, with “advanced nuclear weapons.”

The underground city of Derinkuyu

Another incredible feat of ancient engineering. Thousands of years ago, ancient people excavated hundreds of meters into the Earth, building one of the greatest ancient underground cities on Earth.

This incredible underground city has challenged the views and theories of archaeologists and engineers ever since its discovery.

Many mysteries engulf this underground city. No one has been able to understand why and how it was built.

While some authors indicate it was created to protect its inhabitants from climate change, extreme temperatures or even war, there are others who believe that its purpose is far more mysterious.

Giant Stone Spheres

These giant stone spheres have been present from Costa Rica to Bosnia & Herzegovina, they come in all sorts of sizes. They were first found in South America in the 1930s by workers who were clearing jungle to make way for a plantation of bananas.

South American legends say that hidden within the rocks are unimaginable treasures. This has led to the destruction of many of these spheres by people who did not recognize their historical value. Despite the fact that many of these spheres were destroyed, no one has ever found anything inside them. Similar spheres can be found in Europe in Bosnia & Herzegovina near Visoko.

No one can explain what these giant stone spheres are made for.

14 million-year-old vehicle tracks

According to a researcher called Dr. Koltypin, millions of years ago advanced technologies existed on Earth, and the traces we see in the above image were left behind by vehicles 14 million years ago

As noted by Russian Geologists, these mysterious traces are at least 14 million old and were left behind by “vehicles” that belonged to a currently “unknown ancient civilization” that inhabited our planet in the past.

Many researchers believe that we are not the first society to rule over this planet. In fact, a number of authors have claimed that many other advanced civilizations called this planet home in the past.

According to Dr. Koltypin and many other archaeologists, which have adopted new ways of thinking, these ancient “car tracks” are one of the best-preserved pieces of evidence which undoubtedly prove the existence of highly advanced ancient civilizations that inhabited our planet in the distant past.

2 billion-year-old Natural Nuclear Reactor

In 1972, researchers confirmed the discovery of a set of Natural Nuclear Reactors in Gabon. Ever since, scientists have scratched their heads trying to understand how it is possible that these nuclear reactors developed in Gabon two billion years ago, and did not come into existence at any other place on the Planet.

As claimed by experts, more than two billion years ago, parts of the African uranium deposit spontaneously underwent nuclear fission. According to scientists, this mysterious “natural” nuclear reactor had the ability to produce modest energy. Scientists estimate the Oklo reactors would have had samples with roughly 3.6% uranium-235 — that’s close to the enrichment threshold of modern nuclear reactors.

A Massive knife discovered underwater

Not much can be found about this mysterious image, but we’ll include it just for fun.

We see a massive knife, held by three scuba drivers somewhere on Earth’s ocean.

The image has been widely shared among people on social networks, and many consider it evidence that, before written history, perhaps tens of thousands of years ago, giants walked on Earth.

More than likely, it’s a prop that ended up somehow in the ocean, but who knows for sure?

2.8 Billion-Year-Old Spheres balanced within one-hundred thousandths of an inch from absolute perfection have created confusion among experts.

They vary in size from 30 – 50 mm in diameter and have perfectly concentric grooves around the center as if they were molded. Inside the hard “shell” some have a spongy substance, while in others it resembles charcoal.

Man-Made Artifacts, or the result of mother nature?

Called the Klerksdorp spheres, the enigmatic artifacts are considered by many authors as the ultimate evidence of pre-human civilizations existing on Earth billions of years ago.

However, given their controversial age, mainstream scholars argue they are the product of mother nature.

The Spheroid objects found in Africa date back to a time when humans did not exist on Earth. The mystery objects are elliptical in shape with rough ridges around the center.

Having curious ‘design’ elements on their surface, some authors have argued that the enigmatic spheres are the result of intelligent design.

According to Michael Cremo (Michael A. Cremo (born July 15, 1948), also known by his devotional name Drutakarmā dāsa, is an American freelance researcher who identifies himself as a Vedic creationist and an “alternative archaeologist”) and other researchers of prehistoric culture, these spheres add to a body of evidence suggesting intelligent life existed on Earth long before a conventional view of history places it here.

Suggestions that Earth was inhabited by different lifeforms in the distant past, millions if not billions of years ago, has created countless debate among researchers and authors.

Tests performed on the spheres have yielded controversial results.

According to Biblioteca Pleyades, a man called John Hund who acquired one of the spheres took it to the California Space Institute at the University of California in order to find out more about the curious artifacts.

“It turned out that the balance is so fine, it exceeded the limit of their measuring technology,“ and these are the guys who make gyrocompasses for NASA.

However, this statement was later subtracted by the California Space Institute which denied that anyone told Hund that the object had the extraordinary properties.

According to their statement, there have been “some error in transmission” and that Hund had completely misunderstood the information regarding these objects.

The mystery sphere acquired by Hund is balanced to within one-hundred thousandths of an inch from absolute perfection.

Nobody knows what these stones are.

One NASA scientist told Hund that they do not have the technology to create anything as finely balanced as this.

Hund said the only way that either nature or human technology could create something so finely balanced would be in zero gravity.

A letter from Mr. Hund, made available by Biblioteca Pleyades offers more details about the enigmatic objects:

The existence of the sphere came to my attention ca 1977 while removing endangered rock engravings from the site where pyrophyllite or “wonderstone”, as it is commonly known in the region, is mined on the farm Gestoptefontein (meaning plugged fountain) near the little village of Ottosdal about 110 km from Klerksdorpin South Africa’s Northwest Province.

I was intrigued by the form of the spheres, grooves around the middle and the fact that they are as hard as steel, while the material (pyrophyllite) in which they are found, is as soft as limestone with a count of only 3 on the Moh scale. As you probably know, pyrophyllite (Al2 Si4 O10 (OH)2) is a secondary mineral and the deposits were formed by a process of sedimentation. On Gestoptefontein volcanic activity was responsible for the forming of outcrops varying in height from about 10 to 100 meters. The smooth and relatively soft surface on the slopes were ideal for the prehistoric dwellers (San) to make their engravings of animal and abstract designs.

On Gestoptefontein these outcrops were “swan” into huge pieces by means of twisted steel cables running zig-zag on pulleys for several kilometers. These blocks were then sawn by the same method into more manageable pieces of about 500 x 500 mm. Occasionally the “sawing cable” got stuck on one of the metal spheres embedded in the pyrophyllite.

They vary in size from 30 – 50 mm in diameter and have perfectly concentric grooves round the center as if they were molded. Inside the hard “shell” some have a spongy substance, while in others it resembles charcoal.

When only partly embedded so that they can be seen on the surface, they are not all spheres, but some are also oblong in form.

Andries Bisschoff, a former professor of the University of Potchefstroom argues the curious objects are limonite concretions.

According to research performed on the spheres, they are found in pyrophyllite a secondary mineral which is quite soft.

The spheres have a fibrous structure in the interior with a shell around them.

The spheres are very hard and according to researchers, it is nearly impossible to scratch them.

According to Roelf Marx, curator if the museum of Klerksdorp, South Africa, the spheres are harder than Steel.

Evidence of alien life is being covered up by NASA, according to a researcher from Buckingham University.

NASA is hiding fossil footprints of extraterrestrial activity on the surface of Mars, said Barry DiGregorio, who works at the Center for Astrobiology at the University of Buckingham (United Kingdom) and plans to publish a report promising to reveal all hidden details to the public.

DiGregorio plans to release a ‘bombshell report’ which will reveal, once and for all, how NASA is well aware of this discovery, and how the American Space Agency has chosen to keep the truth hidden from the public.

According to the researcher, who has already been dubbed as a ‘controversial scientist’ by numerous internet new outlets, NASA might be ignoring the discovery because of its plans for a manned mission to Mars in the 2030’s.

However, despite the fact that Dr. DiGregorio plans to reveal the truth to the public, NASA says that the shapes captured in the images from Mars which DiGregorio claims are evidence of alien activity are nothing more than rock crystals that are still being investigated.

DiGregorio specializes in studies of microscopic life found on Earth.

The expert argues how some of the images beamed back by the Curiosity rover show clear evidence of patterns similar to Ordovician trace fossils found on Earth.

According to the researcher from the University of Buckingham, there’s evidence of trace fossils on Mars.

These are made as living beings go on about their lives, leaving behind footprints like burros and waste, rather than the remains of the creatures themselves.

DiGregorio believes how the fossils on Mars may represent evidence of soft-bodied creatures that may have once existed on the surface of the red planet.

In an interview with the Daily Express, the researcher explained:

“If not trace fossils, what other geological explanations will Nasa come up with?”

“Nasa has turned its back on trying to get the data on this. The order came down from HQ that they should move the rover on to the next point. They didn’t feel it was important enough to look at, I thought that was very odd, despite the fact Gale Crater was host to probably a series of lakes for billions and billions of years. We’re talking about something that might have been equivalent to the Ordovician period on Earth.”

NASA, on the other hand, claims how DiGregorio’s discovery is most likely crystals.

“The crystals theory does not add up. The crystals do not branch or twist. We are talking about something that could have been similar to the Ordovician period on Earth,” he said in reference to the geological period that occurred between 485 and 444 million years ago.

The agency ordered Curiosity, claims the British scientist, to continue its journey without meticulously studying the ‘fossils’ found in the Gale crater area, which was supposed to be a lake area billions of years ago.

And despite being called out for his claims, DiGregorio isn’t the only one who believes there could have been living on the surface of Mars.

In the past, numerous claims have been made about Mars and how the red planet may have been inhabited at one point.

Dr. John Brandenburg, for example, is another scientist who claims that Mars was home to alien life.

However, and unlike DiGregorio, Dr. Brandenburg indicates that Mars was once home to complex alien life, rather than simple soft-bodied creatures, as proposed by DiGregorio.

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