Archaeologist Klaus Schmidt announced the discovery of Göbekli Tepe in Turkey in 2008. It’s a huge, carved stone structure that appears to date back to 11,000 BCE. That’s about 6,000 years before Stonehenge!

The best guess is that it’s the first temple ever built by mankind. It includes pillars, stone rings, and drawings of animals.

But here’s where the mystery comes in – our human ancestors didn’t live in groups yet. There was no “civilization,” they were hunter-gatherers. There were no villages, no architecture, and no organized religion – they didn’t even have the stone tools you’d presumably need to build such a thing!

So what’s a gigantic, human-built gathering spot doing out there in the desert? We still don’t know.

Archaeologists are stumped by the “White Shaman Rock” in the Lower Pecos River Canyon in southwestern Texas. This 24-foot cave painting is stunning to behold and seems to depict warriors and tribal members either fighting or contacting spirits using peyote.

The Huichol tribe is responsible for many of the cave paintings in the area. But no one is really sure how the paintings relate to the tribe as they spent their life in the remote regions of the Sierra Madre mountains to get away from European settlers.

Discovered in 1902, the Hypogeum of Sal Saflieni seems to be a sanctuary or even a burial place of some kind. This preserved subterranean labyrinth was in use from 4000 to 2500 BCE. The Hypogeum’s structure has three levels, and in those three levels, you’ll find ornate designs and architecture carved out of the rock.

But perhaps the most intriguing part is the “Oracle Chamber.” Speaking inside at a normal volume amplifies the voice a hundred times, allowing it to carry through the structure.

No one knows if it was designed intentionally. Nor does anyone know what it was used for.

Head on to the northern Xieng Khuang province of Laos. There you’ll find a strange collection in the countryside. The Plain of Jars is believed to be 2,000 years old.

Perhaps they played a part in ancient funeral rites?

The jars are made from sandstone. They weigh at least a ton too.

You’ll find the jars in an area that suffered during the American “Secret War,” which also happened to damage many of the jars. Visiting the site remains limited as it’s not yet been cleared of active cluster bombs.

Cuzco, Peru boasts perfectly fitted boulders known as Saksaywayman. Some weigh over 200 tons. The structure predates the Incas, though there is no specific construction date.

Saksaywayman is a fortress and a ceremonial location. It is a site that truly impresses. A piece of paper would not fit in between the rocks, and for an ancient people without our modern technology, that is extraordinary.

Some say the people who build them must have used a liquid extracted from plants that rendered the boulders to be lighter and more malleable. Others have proposed that heat forced the rocks together.

It could have even been constructed from a wooden template.

In the peat bogs of Northern Europe, hundreds of incredibly well-preserved human cadavers were discovered as far back as the 18th century. We’re talking bodies forensically dated as far back as 8,000 BCE!

The famous “Tollund Man” was discovered in 1950 by two Danish farmers. Tollund Man lived in the Pre-Roman Iron Age of the 3rd century BCE. His stomach contents were used to find out when he lived.

Researchers discovered other corpses that varied in terms of age, sex, and social standing. And yet the corpses seem to have been victims of execution. Researchers can only speculate that they may have been sacrifices or outcasts.

Mysterious stone spheres unearthed in the 1940s in the Diquis Delta of Costa Rica were discovered by the United Fruit Company. The stones range in size from a few centimeters to over two meters in diameter. Some weigh as much as 16 tons!

These mysterious spheres are man-made objects all formed from granodiorite.

Many of the stones are now privately owned, but their mysterious origins are something that researchers have yet to unearth.

It was German archeologist Wilhelm Konig in 1838 who found the clay jars that contained an iron rod encased in a copper cylinder. This led to Konig theorizing that the objects were galvanic cells. They date to the Parthian era, about 200 BCE, which would make the technology truly impressive given the time.

But a leading authority on Iraqi art and archaeology, Elizabeth Stone, says that experts don’t subscribe to the battery theory.

The alternative theory is that they were for storing scrolls. The scrolls would be wrapped around the iron rod, and contained in the copper cylinder. Similar objects called the Seleucia vessels from a nearby ancient city allowed researchers to share the theory.

Smith College Art History professor Dr. Marjorie Senechal had her students build replicas of the device, producing voltage. If they really were batteries, then what exactly were they used for?

A Greek ship sank in the Mediterranean sometime between 70 and 60 BCE. The wreck was discovered in 1900 and divers were able to salvage three pieces of bronze comprising a device that became known as the Antikythera mechanism.

The shoebox-sized artifact has puzzled scholars for more than a century. The sophistication of its gears and internal workings surpasses Greek technology of the time.

It wasn’t until the late 20th century that X-rays of the artifact allowed researchers to discover that it was designed to track astronomical movements. It’s basically an ancient computer – but how did they build something of such advanced construction and intricate precision?

Egypt isn’t the only place that boasts ancient pyramids. Greece has the Hellenikon Pyramid.

Experts believe the structure was erected as a monument for fallen warriors, though the pyramid’s walls never revealed anything to provide evidence of an actual tomb.

The Hellenikon is certainly intriguing, with a history shrouded in mystery. Not to mention that it was supposedly built in 2720 BCE, making it way older than the Egyptian pyramids.

Western Bolivia’s Sajama lines were discovered in 1932 by Aimé Felix Tschiffely. Thousands of lines measure between 3 to 10 feet wide individually and connect 8,700 square miles of an intricate web-like design.

It may very well be the largest archaeological site in the world!

And yet no one has provided a clear answer as to what the lines are for. Scientists speculate that they were created by the indigenous people who lived near the Sajama volcano for reasons unknown. Some believe they were used for religious purposes.

Easter Island is a place of mystery. The famous Polynesian land is home to an intricate series of glyphs believed to be writing or proto-writing. It’s a much earlier form of communication, relying on symbols rather than words.

They were first discovered by Eugene Eyraud in 1864. Dated to 1200, the imagery on the glyphs resembles that of other religious signs found around that location.

The symbols were carved using small obsidian flakes or shark teeth. Scientists have yet to discover their meaning or if they have links to outside cultures.

If Rongorongo is an entire language all its own, then it is a very unique one that could have existed only on the island.

The Sumerian King List is a listing of all Sumerian kings. That includes their dynasties, locations, and times in power. This 3rd millennium BCE artifact provides an interesting take on history as there are mythological elements listed on it.

The King List includes events like the Great Flood and the tales of Gilgamesh. These are the stories often referred to as fables or legends!

Some think that this is proof that the Old Testament stories are true. Some say that the kings listed were actually gods or demi-gods.

The 12-sided Roman dodecahedrons are hollow with a small circle on each side and pegs jutting out from the connecting corners. And there are hundreds of these strange objects.

The purpose of these odd-looking artifacts is unknown. Historians have suggested everything from fortune tellers to candleholders while some suggested they were for astrological or religious means. They have been dated as far back as the 2nd and 3rd centuries CE.

Suggestions also ranged from them being used to sow winter grains, and even to calibrate water pipes for Roman architects.

There is a sprawling underwater city off the coast of Yonaguni Jima. Japan’s own Atlantis is believed to be at least 5,000 years old! A diver discovered the site in 1995.

What seemed at first to be strange rock formations – formations with perfect right angles and straight lines – later revealed a large stone gateway, carved stairways, and even streets.

Researchers believe that the city slowly became submerged due to rising sea levels over the years. They also believed it to be the city of the Jomon people.

These ruins help provide scientists experience when studying other possible underwater cities found around the planet.

The Nazca Lines are found across the dry, desert plains of southern Peru and are truly fascinating geoglyphs.

They date from between 500 BCE and 500 CE.

100 massive glyphs adorn the site depicting everything from simple lines to much more intricate designs of monkeys, humans, fish, jaguars, and birds.

The symbols are recognizable, but their true purpose remains unknown. They could have been used to give incoming sailors directions, or perhaps they were meant for astronomical purposes.

The Codex Gigas, a massive medieval tome, was said to be written in the 13th century by a monk. He made a deal with the Devil himself in order to finish it. The story goes that the monk was to be walled up alive for breaking his vows. He then promised the others that if they let him live, he would write a book containing all human knowledge in a single day.

The monk sold his soul to Lucifer, as per the legend.

It is an extremely long manuscript that appears to have been written by just one person. In a very short amount of time.

The book requires two people to lift. It was created using more than 160 animal skins and includes the complete Latin translation of the Bible. There are other texts included in the book. And you’ll find medical formulas, texts on exorcisms, and a drawing of the Devil too.

Another mystery of the Codex Gigas is that twelve pages of the original manuscript are missing. Could they have contained satanic texts or a way to conjure the devil? We’ll never know.