Ancient Aliens

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.

The Maya created the most sophisticated calendar systems in the ancient world.

Who are the beings with big heads and giant eyes that seem to have been visiting our planet for millennia? Known by researchers as the "greys,".

There are numerous historical, religious and mythic accounts of ancient civilizations being wiped out by volcanoes, earthquakes, floods, and meteors.

NASA scientists, former astronauts and secret government files all point to the conclusion that there has been contact.

At nearly 14,000 years old, the ruins of Puma Punku are the oldest and most baffling on the face of the Earth.

People on every continent have claimed to see Bigfoot's footprints. And ancient myths and legends speak of an ape-like giant stalking the earth.

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

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?

Angkor Wat, Cambodia, is the world's largest ancient religious temple.