Are sacred places the product of man's reverence for God--or the result of contact with ancient space travelers? Jerusalem's Temple Mount has been called a heavenly gateway. Islam's shrine at Mecca displays a Black Stone believed to have fallen from heaven. And the temple at Baalbek, Lebanon was built on a massive stone structure resembling a landing pad. Did man encounter divine beings at these holy places, or might they have met ancient extraterrestrials?

Could gold be the ultimate link between humans and aliens? A church in southern France is said to hold the key to alchemy--and a gateway to another part of the universe. Locals in Cusco, Peru believe UFO sightings are connected to lost gold at the bottom of Lake Puray. And some believe underneath the Great Sphinx of Giza lies an entire library left behind by extraterrestrials--a library stored on gold.

Throughout the world, ancient rites and rituals are believed to connect humans to another dimension. But just who--or what--are we communicating with? Could today's rituals, such as festivals, coronations and funerals, be based on early man's attempts to emulate ancient alien visitors? If so, what other ancient rituals might find their roots in a kingdom--not of this world?

Might the tools and technology of ancient builders have come from distant galaxies? Evidence suggests that an ancient mountaintop fortress in Peru was constructed with laser-like tools... temples at Vijayanagara India were built to harness cosmic energy... and an acoustic chamber in Malta enabled interplanetary communication. If the ancient builders did use advanced technology, could it prove that aliens visited Earth thousands of years ago?

Scientists are continually challenged by unidentified strains of bacteria with mysterious origins. Could some of our most crippling plagues and epidemics be traced to the darkest voids of space--or even extraterrestrial intervention? During the Black Death of the Middle Ages, people reported bronze flying ships emitting a strange mist. As recently as 2011, NASA scientist Richard Hoover published evidence of life in meteorites. Is it possible that ancient aliens--as small as microbes--have shaped human history?

Mysterious legends and crumbling ruins are all that is left of our planet's lost worlds. But could there be proof of ancient alien visitors hidden among the artifacts of civilizations that have long vanished? Strange carvings suggest the Mayan city of Copan was ruled by the descendants of otherworldly beings. And some believe the ancient Nazca people altered their bodies--and their lands--to signal the star gods to return. Are the astounding accomplishments of lost civilizations merely the products of ancient folklore--or could they have been something... out of this world?

Iron swords forged in blazing hot fires... Gunpowder with the power to tear apart human flesh... And rockets capable of destroying entire cities... Throughout history, advances in technology have lead to the development of powerful weapons - each more deadly than the last. But were these lethal weapons the product of human innovation - or were they created with help from another, otherworldly source?

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?

What is the meaning behind secret messages found throughout Washington, D.C.? Did America's Founding Fathers know something about ancient aliens that the general public did not? And if so, could this knowledge have been incorporated into the symbols, architecture, and even the founding documents of the United States of America?

Mass suicides. Human sacrifices. Unholy rituals. Throughout history, people have claimed to have otherworldly knowledge, and have led followers to commit horrific acts of violence. Are they con men? Are they insane? Or might the voices in their heads really be of an extraterrestrial origin? And if so, did they simply misinterpret the messages they received? Or might there be extraterrestrials with a sinister agenda?

Megalithic monuments linked together by electromagnetic energy... Prehistoric ruins arranged across vast distances in straight lines... And advanced mathematics carved into landmarks more than 5000 years ago. Were ancient man's spectacular structures built by humans alone? Or do they bear evidence of being designed - and interconnected--by otherworldly visitors?

Zombies rising from their graves... Blood sucking vampires damned for all eternity... and humans trapped in a life and death struggle between heaven and hell. For thousands of years, mankind has told tales of encounters with strange, soulless creatures. Are these beliefs merely manmade fabrications - or could there be extraterrestrial origins in earthly encounters with the undead?

Superhuman strength... Supernatural powers... And the awesome ability to fly. Throughout history, mankind has told incredible tales of gods with extraordinary powers. But are these accounts merely tall tales, or could they be based on factual events? If mythical gods really did exist, were they, as ancient astronaut theorists believe, extraterrestrial beings? And could this help to explain the enduring popularity of gods, titans and other so-called "super-heroes"?

Why are humans so different from every other species on Earth? Did we evolve from ape--or is our intelligence the result of contact with an otherworldly source? Could unexplained advances in human evolution be the work of interstellar beings? 10,000-year-old petroglyphs link our ancient ancestors with star beings. Might evidence of alien contact help unlock the mystery of the Creation of Man?

For thousands of years, pyramids were the largest structures on Earth. The best known were constructed in Egypt and Central America, but others have been found all around the world, including in China, Africa and Indonesia. But what purpose did the pyramids serve? Researchers explore strange similarities between all pyramids, as well as the geographic, strategic and otherworldly connections between these mysterious monumental structures.

In 1980, three young military men were sent into a UK forest to investigate strange lights. They reportedly encountered a spacecraft of unknown origin. When one of the men touched it, he claims to have received telepathically a long sequence of binary code, which he later wrote down and translated. The military ordered them to never speak about the incident. Why do such UFO encounters continue to be kept under wraps, and what might they reveal about our ancient past?

Egyptian hieroglyphs depict the use of light bulbs in tombs and secret chambers. And batteries may have been discovered among artifacts from Mesopotamia. Did the Ancients understand electricity, and if so, how did they discover this technology? Might they have had help from extraterrestrials?

Why were ancient civilizations around the world so focused on the Orion constellation? While scientists site many earthly connections, researchers suggest this point in the night sky may have been a so-called Stargate, or entry point, for alien life forms. If extraterrestrials have been visiting Earth for thousands of years, might they have originated from the Orion Nebula?

Was Albert Einstein a genius? Or was he superhuman? Was his genius ‘of this world,’ or was it ‘otherworldly?’ Is it possible, as Ancient Astronaut theorists believe, of an extraterrestrial connection to the scientific genius of famous historical figures such as Albert Einstein, Galileo, Archimedes, and Aristotle?

Across the globe, archaeologists have uncovered ancient tombs filled with strange items and writings. Remarkable similarities have been found at each of the sites. How is it possible that the burial chambers of distant cultures were so similar in design? Ancient Astronaut theorists believe that some of these complicated and technically advanced tombs were designed with the help of extraterrestrials.

They were the messengers of divine knowledge and seers who shared visions of the future. For thousands of years, human civilization has been guided by the words and deeds of ancient prophets, but just who--or what--were these prophets communicating with? Might the experiences of history's prophets be evidence of communication with a heavenly source--or were seers like Elijah and Joseph Smith actually communicating with extraterrestrial overlords? And if so, are there similar prophets at work today?

Erich von Daniken's landmark book, Chariots of the Gods, brought attention to the mysterious phenomena of the Nazca Lines. Hundreds of gigantic lines, some in the shape of animals, geometric patterns and even an alien-like being, extend for miles throughout a remote Peruvian desert. Scholars are divided as to who built them, and why. Some Ancient Astronaut theorists believe that the massive markings have an extraterrestrial connection, and perhaps the ancient people of the region created these gigantic figures in tribute to the gods who visited them. And with one of the largest deposits of nitrates in the world--a key ingredient in rocket fuel and weaponry--could Nazca have been a mining operation for advanced beings in the distant past?

In 1975, Travis Walton claims to have been abducted and taken aboard a space ship inhabited by extraterrestrial beings. Several people witnessed his encounter and nearly 40 years later Walton's story of alien abduction, missing time and mind-telepathy manipulation has not wavered. But researchers say that abductions are not a modern phenomenon. The Hebrew Bible is filled with stories of abductions by otherworldly beings. Jonah, Moses, Ezekiel and Enoch all depict what can best be described as physically being taken to other dimensions and then returned. Is it possible that extraterrestrial beings have been abducting humans for thousands of years and if so, might there be an alien agenda behind the phenomena?

A young man's spiritual journey. A controversial bestseller. And a scientific theory that threatened to change the world. Just what are the facts behind Erich von Däniken and Ancient Astronaut theory? For more than 40 years, his books have sold over 65 million copies worldwide. He is a hero to some, and a heretic to others--but Erich von Däniken's controversial theories have captured the attention of the world and ignited a movement known as Ancient Astronaut Theory. His exhaustive search for the truth about mankind's otherworldly origins have started to gain acceptance with a small but growing number of Ancient Astronaut theorists--men and women who have expanded, and at times refined, von Däniken's findings. Did ancient astronauts really come to planet Earth? And, if so, what was their purpose? And perhaps even more important--will they come again?

They were teachers and destroyers. Mighty warriors who blazed across the skies in gleaming chariots and wielded magical weapons that could bring down mountains. Odin, Frey and Thor. The gods worshipped by the Norse Vikings were fearsome and mysterious, but were these beings truly divine, or is there, perhaps, an extraterrestrial connection? The Norse were among the most technologically advanced cultures of the ancient world. They were epic explorers who embarked on oceanic voyages to Africa and the Middle East and even reached North America at least 500 years before Christopher Columbus. Were the Norse guided by powerful gods, or could the super-beings that guided the Vikings have actually been visitors from another planet?