The History Channel

Angkor Wat, Cambodia, is the world's largest ancient religious temple. Within its megalithic ruins, researches have discovered a depiction of a species of dinosaur--a stegosaurus. But how could the ancients have had knowledge of animals that mainstream science says died out millions of years ago? Why are dinosaurs extinct? Did an alien race of beings kill off the dinosaurs to make room for humankind?

The Maya created the most sophisticated calendar systems in the ancient world, and according to many scholars their Long Count Calendar will come to an end on December 21, 2012. What does this mean for mankind? Some researchers believe it will usher in the return of Bolon Yokte--a mysterious god associated with creation and war. Could this god actually be an extraterrestrial as some ancient astronaut theorists believe? Other scholars believe the end of the calendar will bring about a series of catastrophic events that may threaten the very existence of mankind. They point to a rare galactic alignment that will coincide with the end of the Mayan calendar as proof of an impending geological catastrophe. If these doomsday prophecies prove to be true, will it mean the end of the world as we know it? Or could it reveal some profound truth about the origins of the human race?

Might an examination of Leonardo Da Vinci's masterful paintings, highly technical hand-drawn sketches, and private journals reveal knowledge of otherworldly technology and extraterrestrial beings?

Angkor Wat, Cambodia, is the world's largest ancient religious temple. Within its megalithic ruins, researches have discovered a depiction of a species of dinosaur--a stegosaurus. But how could the ancients have had knowledge of animals that mainstream science says died out millions of years ago? Why are dinosaurs extinct? Did an alien race of beings kill off the dinosaurs to make room for humankind?

Ancient underwater cities can be found around the globe, but could these aquatic worlds be the ruins of unknown civilizations--or even proof of extraterrestrial visitations? The infamous tale of the long lost city of Atlantis may be a preserved memory of an ancient alien metropolis. Beneath Lake Titicaca in Peru, the ruins of recently discovered temples support local legends of an underwater UFO base. Ancient Indian texts, known as Sangams, describe sunken cities where aliens and humans intermingled thousands of years ago. Who could have built the 600-foot stepped stone structure off the coast of Japan--a site that may predate the Egyptian pyramids by thousands of years? Could evidence of ancient alien contact lie buried in Earth's deepest oceans?

Myths and legends have long been regarded as fantastic stories that describe powerful gods, mutant giants and fearsome monsters. But why do so many different cultures, separated by vast distances, tell the same stories? Is it possible that myths and legends were really eyewitness accounts of ancient astronauts descending to Earth? Ancient texts are filled with stories of gods interacting with humans, offering wisdom, technology, and even impregnating women. Could the demigods of mythology have been the offspring of alien and human unions? If so, could aliens have supplied the Missing Link that accelerated human evolution, advancing our civilization and making us who we are today?

For thousands of years, there have been places around the world considered dangerous to humans. Might these locations hold the key to an otherworldly connection? At Australia's Black Mountains, local myths speak of ancient serpent gods and hikers disappearing. Every year hundreds are drawn to a dark forest at the base of Mount Fuji in Japan--to commit suicide. What causes these places to be evil? Could there be evidence that past extraterrestrial activity lead to the negative energy in Earth's evil places?

Is it possible that sightings of alien beings or UFOs may actually be evidence of time travelers from the future? And might ancient astronauts actually be time travelers from our future? Scientists explore the theoretical possibility of time travel. How can it be achieved? And what might people from 10,000 years in the future look like?

The Mayan civilization dominated Central America for nearly 2000 years, but by the 9th century A.D., the great Mayan cities were abandoned, and the Mayan people vanished. What could have happened to this advanced culture? Might the Maya have left clues as to how they surpassed other cultures in science, mathematics, time keeping, and most importantly, astronomy? In recent years, hieroglyphs have been decoded to reveal that the Maya were able to accurately predict shifts in the Earth's axis every 26,000 years. Inscriptions on the sarcophagus of their most prominent ruler, King Pakal, tell of a journey to the Milky Way. And a sophisticated calendar foretells of the end of the world in 2012. Most striking is their belief that knowledge was passed to them by otherworldly beings who descended from the sky. Could the ancient Maya have actually conspired with extraterrestrial visitors to plan the future--and even the very end of the world?

December 21, 2012: a prophetic date delivered in stone by the ancient Maya. Revered by scientists for their extremely accurate calendars, the Maya are also known for their mysterious ability to predict unsettling events so many are taking the December date seriously. On this date a rare galactic alignment will take place and coincidentally, as the alignment happens, our sun will be entering its most violent solar storm cycle. And, all of this comes at a time when scientists believe Earth s magnetic defense shield, which protects us from dangerous solar radiation, may be compromised. Our planet may become paralyzed. People are heeding the warning and getting prepared, including a group of everyday Americans learning how to fend for themselves and live off the grid.

The world is coming to an end on December 21, 2012! The ancient Maya made this stunning prediction more than 2,000 years ago. We'll peel back the layers of mystery and examine in detail how the Maya calculated the exact date of doomsday. Journey back to the ancient city of Chichen Itza, the hub of Maya civilization deep in the heart of Mexico's Yucatan Peninsula, to uncover the truth about this prophecy. The Maya were legendary astronomers and timekeepers--their calendar is more accurate than our own. By tracking the stars and planets they assigned great meaning to astronomical phenomena and made extraordinary predictions based on them--many of which have come true. Could their doomsday prophecy be one of them? In insightful interviews archaeologists, astrologers, and historians speculate on the meaning of the 2012 prophecy. Their answers are as intriguing as the questions.

The Hopi people have warned us that the world is headed for extinction. Based in the Arizona Desert, the Native American tribe of the Hopi has been prophesying about the fate of society for centuries. They have accurately predicted the coming of the settlers to their land, the birth of telecommunication, and the worldwide spread of the internet. The Hopi believe that our actions have caused the earth to become out of balance which will lead to a cataclysmic great purification of the planet that few will survive. To herald these end times, the Hopi believe that a blue star will arise in the heavens, followed by a great shaking of the earth. These prophecies have been passed down from generation to generation and warn of massive earthquakes, tsunamis and super-volcanos that threaten the lives of millions. The Foster family of Illinois is prepping in their own way to be ready for the end.

The Italian writer Dante called the sin of pride the "Chief of All Sins" -- the sin of Satan himself. The sin of pride was condemned by the Bible and the philosopher Socrates, while Romans and Vikings made it their greatest virtue. The sin of pride is thought to have led to the fall of Satan but strangely enough, the most famous story about Satan is not in the Bible. So what is the origin of the sin of pride?

Informational programming.

Informational programming.

Informational programming.

Informational programming.

For as long as mankind has questioned his own beginnings, he has been obsessed with how it will all end. Stephen Wohlberg is a Californian preacher who eagerly awaits--along with his wife and young children--the apocalyptic end of the world. Two British researchers propose a new theory and show new evidence that Sodom and Gomorrah were destroyed by the fallout from an asteroid impact over 5,000 years ago. They believe the event was so devastating that it left a mark in every single Mediterranean religion, and actually gave birth to Western ideas of the Apocalypse. Today, global destruction does not require divine intervention: former Soviet nuclear defense specialist Stanislav Petrov tells the story of the day he saved the world from World War III.

Ancient underwater cities can be found around the globe, but could these aquatic worlds be the ruins of unknown civilizations--or even proof of extraterrestrial visitations? The infamous tale of the long lost city of Atlantis may be a preserved memory of an ancient alien metropolis. Beneath Lake Titicaca in Peru, the ruins of recently discovered temples support local legends of an underwater UFO base. Ancient Indian texts, known as Sangams, describe sunken cities where aliens and humans intermingled thousands of years ago. Who could have built the 600-foot stepped stone structure off the coast of Japan--a site that may predate the Egyptian pyramids by thousands of years? Could evidence of ancient alien contact lie buried in Earth's deepest oceans?

Myths and legends have long been regarded as fantastic stories that describe powerful gods, mutant giants and fearsome monsters. But why do so many different cultures, separated by vast distances, tell the same stories? Is it possible that myths and legends were really eyewitness accounts of ancient astronauts descending to Earth? Ancient texts are filled with stories of gods interacting with humans, offering wisdom, technology, and even impregnating women. Could the demigods of mythology have been the offspring of alien and human unions? If so, could aliens have supplied the Missing Link that accelerated human evolution, advancing our civilization and making us who we are today?

For thousands of years, there have been places around the world considered dangerous to humans. Might these locations hold the key to an otherworldly connection? At Australia's Black Mountains, local myths speak of ancient serpent gods and hikers disappearing. Every year hundreds are drawn to a dark forest at the base of Mount Fuji in Japan--to commit suicide. What causes these places to be evil? Could there be evidence that past extraterrestrial activity lead to the negative energy in Earth's evil places?