15 Of The World's Greatest Unsolved Puzzles

Ever since the dawn of time, our world as we know it has been covered in mystery. After all, that's how legends were born, in the attempt to explain the unexplainable. With the evolution of science and technology, it's only natural that we expect most phenomena to be explained. We would presume codes and encrypted messages are no longer a challenge for the world's top codebreakers. Well, think again!

Although some myths have been busted, and some mysteries have been explained, there are still many puzzles that remain locked with a key we do not yet have access to. Most spine-tingling impenetrable enigmas revolve around life on Earth, the soul, and whether we are alone in the vast Universe. There are many other questions still left unanswered. Is time travel possible, are there other dimensions, did some extremely evolved civilizations roam the planet before us? Besides these, there are a number of mind-boggling unsolved criminal cases and disappearances that make us wonder whether some unnatural force had something to do with them.

15 DB Cooper

On November 24, 1971, DB Cooper hijacked a Boeing 727 in the airspace between Portland and Seattle, demanding a ransom and parachute, while claiming to have a bomb in his briefcase. He extorted the $200,000 in ransom and parachuted from the aircraft, never to be seen again. Despite the extensive manhunt and FBI investigations, DB Cooper was never found, as if he vanished into thin air. The DB Cooper hijacking remains the only unsolved air piracy case in American history.

14 The Zodiac Killer

For ten whole months in the late 1960's, northern California and the entire San Francisco Bay Area have been terrorized by a serial killer the authorities nicknamed the Zodiac Killer. To this day, no one knows the true identity of the killer. Local police and press received a series of four mind-bending letters in the form of encrypted messages, hence the name of the Zodiac Killer. Only one was deciphered, and it contained a disturbing message regarding the killer's thirst for blood. The other three remain a mystery, and many assume they might contain clues to the motifs, operating mode, and possible location of other victims.

13 Jack the Ripper

The series of murders that terrorized the Whitechapel district in London during the fall of 1888 have become the subject of many stories and movies. It's unsure whether the crimes were the work of one man alone or multiple persons. However, the brutal murders were attributed to one persona, Jack the Ripper. All 11 known victims were impoverished prostitutes. In some cases, the bodies were found within minutes after the killer fled the scene, which is particularly strange given the fact that the Ripper took his time to mutilate his victims.

12 The Lost City of Atlantis

The first records we have of the Lost City of Atlantis come from Plato who, in his dialogue Timeaus, describes an island located “in front of the Pillars of Hercules.” His portrayals raise much controversy and debate on whether the place really exists or Plato simply made the whole thing up. Atlantis was a world power in the 10th millennium BC, it attacked Athens and failed, and sank in a single day. Stories tell of their advanced technology, mastering science and engineering skills that were thousands of years ahead of their time.

11 Phaistos Disc

In 1908, Italian archeologist Luigi Pernier discovered a mysterious disc in the Minoan Palace site of Phaistos, on the Greek island of Crete. The disc, made from fired clay, contains a series of unknown hieroglyphs, and remains one of archeology's most famous puzzles. Scientists believe the Phaistos Disc dates from sometime in the second millennium BC, and might contain clues to the civilization's sudden and unexplainable boom, as the Minoan civilization is considered the first organized culture in history.

10 Nazca Geoglyphs

Also known as the Nazca Lines of Peru, the extremely large geoglyphs of the Nazca civilization were discovered in the late 1930's, about the same time man began mastering the art of flight. Made from shallow lines dug into the earth, the amazing geoglyphs depict all sorts of members of the natural world, from monkeys and birds to spiders, sharks, orcas, and flowers. What's even stranger is that their precision is flawless, while at the time they made the geoglyphs, the Nazca people presumably had no way of seeing their work from above.

9 Voynich Manuscript

A mysterious hand-written illustrated codex that has been carbon dated to the early 15th century continues to fascinate scientists as they have all failed to decipher it. The Voynich Manuscript originated from Italy, and its pages are filled with colorful, yet very bizarre illustrations that range from biology to astronomy, even recipes, but nobody can understand what is going on in there. There are drawings of flowers that belong only to the New World, which had not yet been discovered back then. Some of the plants are still unknown to modern scientists. The language? Completely unrecognizable.

8 Easter Island and the Rongorongo Glyphs

The Moai Head Sculptures scattered all around Easter Island in the southern Pacific Ocean have always stirred the curiosity of researchers. Incredibly large, they had to be moved from the quarry at least 11 miles to the place they sit on today, without the use of wheels, cranes, or large animals. The enigmatic sculptures are the work of the ancient Rapa Nui tribes, and that's not all they left behind. A set of strange glyphs etched onto pieces of wood have been discovered, known as Rongorongo, that appear as a form of writing, not yet deciphered. The glyphs are believed to contain clues to the origin and purpose of the large head sculptures on the island, as well as to the mysterious collapse of the Rapa Nui civilization.

7 Saint Germain

A historical figure by the name of Count de Saint-Germain seems to have appeared several times over the past centuries, always looking 45 years of age. Some records date his birth to the late 17th century, but there are some who believe he was born around the same time as Jesus Christ. The most recent sightings were reported in the 1970's. Many of the world's notable personalities encountered him at one point in their lives, including George Washington, Catherine the Great, King Louis XV, and Casanova. Voltaire himself referred to the Count de Saint-Germain as “a man who never dies, and who knows everything.”

6 Mary Celeste

Mary Celeste was a British-American merchant brigantine, and a classic example of a ghost ship. On December 4, 1872, Mary Celeste was mysteriously found adrift near the Strait of Gibraltar, apparently abandoned. One lifeboat was missing, and so was its crew of ten. What is particularly bizarre is that Mary Celeste had six months worth of food and water on board. There had been no storm, and the crew were all experienced seamen. The cargo was found untouched, the crew's belongings all in place, as well as all valuables. None of the crew were ever seen or heard from again, and Mary Celeste remains one of the biggest unsolved mysteries in maritime history.

5 SS Ourang Medan

In June 1947, an SOS message was picked up from the Dutch freighter SS Ourang Medan, saying: “All officers and captain are dead lying in chartroom and bridge. Possibly whole crew dead.” What followed was an undecipherable Morse code, and a skin crawling message, “I die.” Then silence. The vessel was located in Malaysia, within the Strait of Malacca. When they went on board to investigate the distress signal, they found every single member of the crew dead, lying on the decks, their eyes still open, an expression of terror on their faces. No signs of wounds were found on the bodies.

4 Shroud of Turin

No religious artifact has been able to raise so much controversy as the Shroud of Turin. Believers say it was the very shroud that covered Jesus after his crucifixion, and would therefore bear the signs of his resurrection. Others say it is nothing more than a hoax, while some agree that it did cover a crucified body at one point, but it is not sure whose. Bearing the clear image of the face and body of a crucified man, no one was able to explain how the image could have been imprinted on the cloth, and all experiments to recreate the imprint failed.

3 Bermuda Triangle

A large section of the ocean in the North Atlantic has long been the scene of multiple mysterious aircraft and boat disappearances. Many theories revolve around the causes, from time warps to magnetic fields and even alien abductions. What is sure is that instruments here go berserk. The most famous Bermuda Triangle mystery is the disappearance of the USS Cyclops, who left from Barbados for Baltimore on March 4, 1918 and was never seen again. The vessel and the crew of 306 passengers vanished without a trace. What's more, it seems a gigantic city lies on the bottom of the ocean, with several sphinxes and pyramids that are bigger than Egypt's. Could this be the Lost City of Atlantis?

2 UFO Sightings

Allied pilots during World War 2 used the term foo fighters when referring to mysterious phenomena or possible UFOs in the airspace. Such sightings have been reported since November 1944. Some pilots simply assumed they were secret weapons of their enemies, but they nevertheless remained unidentified. What's even more curious is that both Allied and Axis forces reported seeing foo fighters. There's famous Roswell and Area 51, synonyms for UFOs and aliens, all due to the events on July 7, 1947, when the US Army supposedly found an alien spacecraft. UFO sightings and alien abduction stories are very common across the Globe, and we can't help but wonder how much is actually true.

1 Philadelphia Experiment

During World War 2, radar invisibility was a much sought after feature. In 1943, the SS Eldridge, a US Navy destroyer, became the guinea pig for the most bizarre experiment that presumably took place in history. The purpose was to make the ship, together with all its crew, invisible for the radars. Shortly after the experiment proceeded, the ship was covered in a thick white-green mist, and minutes later became immaterial. It disappeared from sight and radars for five minutes. When it reappeared, most of the crew members were totally or partially carbonized, some showed signs of madness, some were trapped in the metal structure of the ship, and others disappeared. Witnesses claim that during those five minutes, the SS Eldridge appeared in Norfolk, almost 400 miles from Philadelphia. What's even stranger is that the few surviving members of the crew, after being suddenly discharged, miraculously disappeared one by one, some through walls, others even in the middle of altercations.

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