The world is full of amazing things and over the years, scientists have been able to put a lot of answers to some of the toughest questions about some of the most interesting discoveries. But even today, there are still some discoveries in this world that scientists don’t have the answers to, leaving them with plenty of questions to ask. With structures and artifacts still being found today from thousands of years ago, many of the questions revolve around the same thing. Who made them? Who put them there? What is their purpose? How old are they?

Scientists work hard to answer these questions about some of the most amazing things discovered, but certain objects, places, and phenomena still leave them baffled with more questions than answers. Here are 25 things scientists and archeologist have discovered, some of which, are huge tourist attractions today, and the questions they are still asking themselves about them. The truth is, we may never get the answers we want to these questions, due to these mysteries being thousands of years old, but that doesn’t stop scientists from trying to find out even more about them, and why they are here. So, look at this list and see the things that still have scientists stumped.

25 Derinkuyu Underground City - We Still don't know who built it!

In Turkey, there is an underground city known as Derinkuyu, which extends approximately 200 feet and it large enough to shelter over 20,000 people. This underground city is the deepest excavated underground city in Turkey, that has plenty of tunnel passages and shelters.

It’s impressive how homes and shelters were built out of it, forming an 18 level complex, and according to disclose.tv, it is over 110,000 years old.

It is not known who built the city, but it has been proven many different groups lived there over time.

24 Crop Circles - Messages from above

Some of the most famous markings on Earth are crop circles, which generally appear in farmers’ fields, flattening crops in different patterns and designs. The term was coined in the 1980s, and many believe that crop circles are a hoax, trying to play off people’s nature to believe they are created by aliens coming to earth.

Except there is no scientific evidence showing aliens have visited earth to make the circles, and it has been shown on various documentaries that it is possible to man-make them, despite the size of them.

23 The Atacama Skeleton - aliens live among us

Found in the Atacama Desert, the Atacama Skeleton was as close to an animal skeleton as many would think humans have ever found. Its oval-shaped head and large eyes immediately had people thinking alien, but in 2018, CNN reported that the skeleton was definitely human after running DNA analysis on it.

It's definitely human!

So still no proof of aliens just yet, despite many people, even in 2013, thinking that is what it was. In fact, the remains are only dated back 40 years, so it’s not even that ancient but it has everyone asking questions.

22 Lost City Of Atlantis - We found Aquaman!

The City of Atlantis has more lore behind it, as the Greek philosopher, Plato wrote that the majestic city sunk to the bottom of the sea. Others believe it could be in the Bermuda Triangle, while others believe it’s simply just a myth.

The truth is, no one really knows, and even legends and myths have some form of truth behind them.

Many scientists, according to National Geographic, believe the island never existed, and it’s just a story made up that has passed along for so many generations that it has become a treasure that will always be looked for.

21 The Hypogeum Hal Saflieni Temple - A temple for dinosaurs?

The Hypogeum Hal Saflieni Temple, which means ‘underground’ in Greek, dates back to 3300 to 3000 BC and is one of the best prehistoric sites in the world. But many still don’t know the true reason for the temple, as some believe it was a sanctuary, while others think it was a necropolis, due to the fact that over 7,000 individuals have been documented by archeologists according to Cambridge University.

Visitors can walk through the temple that is on the small island of Malta in what was named a World Heritage Site back in 1980.

20 The Great Pyramids - Who knows what secrets they hold?

It’s widely known that the Great Pyramids are tombs for Egyptian Pharaohs as they very much believed in the afterlife, and already archaeologists have discovered plenty about the complex site.

But there are still so many unanswered questions, such as who actually built the monument and how they did it.

Considering at one point the Great Pyramid of Giza was the tallest man-made structure in the world, coming in at over 481 feet fall, it’s a question about how people were able to build it without the tools and technology of today.

19 The Cochno Stone - We don't know where the map leads to

In West Dunbartonshire, Scotland is a large stone called the Cochno Stone, which has groved spirals, carvings, indentations and patterns carved into it. To this day, no one has any idea what they mean.

Known also as the Druid Stone, the stone is 42 feet by 26 feet, and was documented back in 1887, and has over 90 carvings on it.

This 5,000-year-old stone, however, is one of the best known prehistoric pieces of art in existence and has been protected against vandalism. But today, the original meaning is lost, according to ancient-origins.net, with some thinking it is ancient writing, while others lead to the spiritual.

18 Roman Dodecahedron - the world's first fidget spinner!

A Roman Dodecahedron is a small object that is hollow and made of bronze or stone, which has 12 flat pentagonal faces, each with a hole in it. That’s a lot of different shapes for these odd objectives, in which 100 of them have been found, according to the Mathematical Intelligencer.

As it stands, no one has any idea what these objects are or why they were created, and theories have them being everyday objects from candlestick holders to dice, to instruments that determine the optimal sowing date for winter grain.

17 Qin Shi Huang’s Tomb - an entire clay army beneath us

Farmers unearth plenty of things from the ground, but China’s farmers in the Shaanxi province were in for a big surprise when they found the Qin Shi Huang’s tomb. It is one of the most amazing finds of the 20th century and is a life-size terracotta army of Emperor Qin Shi Huang.

Historians believe the clay army was created to protect China’s first emperor after he passed away, but it’s not known where the emperor is located.

Archaeologists discovered over 7,000 statues of warriors and horses in a 20,000 square meter area.

16 The Bolshoi Zayatsky Labyrinths - Just for you David Bowie

Archaeologists from St. Petersburg believe the Bolshoi Zayatsky Labyrinths are over 2500 years old, but they still don’t have a clear idea what they are for.

Their use has changed through history and one suggestion would say it is the border between the real world and underworld, hence the name, the Labyrinth.

But beyond a historical doorway, which would be very hard to prove, there are 850 heaps of boulders and 35 labyrinths, and they are definitely a mystery in Russia, with excavations, according to the Russia media, resulting in findings of bones.

15 Stone Spheres In Costa Rica - Volcanic balls

In Costa Rica there are these giant stone spheres that date back to 600 AD and were made by gabbro, a rock that forms from molten magma, the stuff from volcanoes. People carved these massive balls of stone, most likely using smaller stones to shape them, according to archaeologists who study the ancient rocks.

No one really knows what they were made for, though some suspect they were used for Astronomical purposes, but the reality is, no one is sure.

Just giant stones sitting in Costa Rica that have been added to the UNESCO list of World Heritage Sites.

14 Göbekli Tepe - We don't know what it used to be

Göbekli Tepe is an archaeological site in Turkey that dates back almost 12,000 years, and is a site built around the same time as the last Ice Age ended. It’s older than Stonehenge by 6,000 years, so it’s pretty old. And despite having plenty of time to identify the reason for the site, archaeologists still have no idea what the site is for.

There are more than 200 pillars in about 20 circles, at a height of about 20 feet each, weighing 10 tons, each fitted into the bedrock. It was excavated in 1996, and it is believed to be a sanctuary. It was added to the UNESCO World Heritage Site list in 2018.

13 Shroud Of Turin - A man of the cloth?

The Shroud of Turin is a linen cloth with a negative image of a man on it, which many claims is Jesus of Nazareth. It is currently housed in the Cathedral of Saint John the Baptist in Turin, which is in northern Italy.

Some claim it is the actual burial cloth that Jesus was wrapped in.

The interesting part is, there is no history on the Shroud before 1353, and even then, history really isn’t known until 1390. That leaves the shroud in plenty of controversies, as no one knows for certain how it was made, how the image was put on it, and how it has survived all these years.

12 The Copper Scroll - The scroll of truth!

The Copper Scroll is part of the Dead Sea Scrolls, but it is vastly different, considering it was not written on parchment or papyrus like the more famous scroll is, but rather, was written on a metal, copper mix.

And unlike the Dead Sea Scroll, it is not a literary work, but many believe it is a map to various items of gold and silver.

It was found in March of 1952 and sent to Manchester University's College of Technology in England to unroll the scroll by having it cut into sections, allowing the text to be read.

11 The Longyou Caves - We just want to know why!

The Longyou Caves were discovered in 1922, and to date, 24 caves have been found. The most interesting thing is that no one has any idea who built them and why. Engineers are amazed by the size of the caves, considering they were man-made.

They are very large, with some of them being 11,000 square feet, reaching heights of 98 feet.

Those are some tall ceilings! Speaking of the ceiling, they are all the same, with parallel bands running through them, giving it a unique design. It’s a tourist attraction in China, and many date them back to 212 BC.

10 The Voynich Manuscript - Maybe it's A book on how to understand women

It’s hard to believe the Voynich Manuscript was discovered by an antique bookseller in 1912 according to livesciebe.com, but the 250 page book was found with so many unknown writings in it, that to this day, no one has been able to read.

The book includes an unknown alphabet, illustrations, including human figures, medicinal herbs and Astrological signs, and plenty of things to make archeologists wonder what the author is trying to say.

Some think it’s a code, some believe it’s in an unknown language, but truth is, as of today, no one has been able to decipher it.

9 The Khatt Shebib - Who built the wall?

Everyone knows about the Great Wall of China, but there is another famous wall that has kept archaeologists pondering. In Jordan, the 93-mile Khatt Shebib was discovered in 1948 when a British diplomat was flying over Jordan, according to livescience.com.

As the diplomat said, he saw a "stone wall running, for no obvious purpose, across country".

Aerial photography shows the wall runs north and south at a distance of 66 miles, and a section where two walls run side by side. Today, Jordan archaeologists still have no idea who built it, when it was built, and what the purpose of it was, other than of course, to keep someone out.

8 Mystery Hill - More like America's Hobbiton

Mystery Hill is also called America’s Stonehenge, as it consists of a number of large rocks and stone structures around a 30-acre region within the town of Salem, New Hampshire.

Not much is known about the now tourist attraction, as many don’t know the origin or purpose of the stone structure.

Though some believe that the man who called it Mystery Hill, William Goodwin, may have built it himself, according to the Detroit Free Press, and there is no cultural significance between this version of ‘Stonehenge’ and the one in England.

7 Puma Punku - And maybe a door to Nike as well

Puma Punku is part of a large temple complex in Bolivia, and it is believed to be dated around 536 AD or later. The name means ‘The Door to Puma’, and there are many different courts inside the complex.

Today’s understanding on the complex is pretty vague, and limited due to the age of the site, as many of the metal and stone carvings have disappeared, and there was a lack of a written record at the time.

Add in treasure hunters looting the site, it has left even more mystery, as it is not known who built the structures, how they built them, or why they were built, to begin with.

6 Nazca Lines - The Original Art Attack

In South Peru there are a series of trenches in the Nazca Desert known as the Nazca Lines, which were created back in 500 BC. They can range between 4 to 6 inches deep, and 0.4 to 1.1 kilometers wide and a combined over 1,300 kilometers in length.

The lines are made into some amazing shapes, such as a hummingbird, heron, whale, spider, and a pelican, amongst many others, and they are best seen from the air.

It isn’t known why the people in Peru removed the natural reddish pebbles and uncovered the white ground underneath, but many suspect some kind of faith reason.