Ancient alien theorists reveal secret codes various civilizations have been using. See more in this Ancient Aliens marathon. Watch all new episodes Fridays 9/8c; Stream Next Day, and stay up to date on all of your favorite shows on The HISTORY Channel website at http://history.com/schedule. ...

Ancient astronaut theorists believe there was an otherworldly presence inhabiting these mysterious sites. See more in this Ancient Aliens compilation. Watch all new episodes Fridays 9/8c; Stream Next Day, and stay up to date on all of your favorite shows on The HISTORY Channel website at ...

Throughout history, incredible stories have been told of the dead rising from their graves, mummies journeying into the afterlife, and people on the brink of death mingling with deceased relatives in a celestial netherworld. See more in Season 9, Episode 6, "Alien Resurrections." Watch all ...

Check out these alien connections in India! See more in this Ancient Aliens compilation. Watch all new episodes Fridays 9/8c; Stream Next Day, and stay up to date on all of your favorite shows on The HISTORY Channel website at http://history.com/schedule. #AncientAliens Subscribe for more ...

For thousands of years, in cultures throughout the world, people have practiced elaborate techniques to preserve the human body after death. See more in Season 9, Episode 5, "Secrets of the Mummies." Watch all new episodes Fridays 9/8c; Stream Next Day, and stay up to date on all of your ...

Researchers find mysterious aztec codices in Mexico City. See more in this clip from Season 21, Episode 7, "Mysteries of the Aztecs." Watch all new episodes Fridays 9/8c; Stream Next Day, and stay up to date on all of your favorite shows on The HISTORY Channel website at ...

Follow David Childress as he investigates mysteries around the world. See more in this Ancient Aliens compilation. Watch all new episodes Fridays 9/8c; Stream Next Day, and stay up to date on all of your favorite shows on The HISTORY Channel website at http://history.com/schedule. ...

These unexplainable theories surrounding children and aliens are finally disclosed. See more in this Ancient Aliens compilation. Watch all new episodes Fridays 9/8c; Stream Next Day, and stay up to date on all of your favorite shows on The HISTORY Channel website at ...

Check out these unexplainable alien connections. See more in this Ancient Aliens compilation. Watch all new episodes Fridays 9/8c; Stream Next Day, and stay up to date on all of your favorite shows on The HISTORY Channel website at http://history.com/schedule. #AncientAliens Subscribe for ...

Check out these out of this world alien theories. See more in this Ancient Aliens marathon. Watch all new episodes Fridays 9/8c; Stream Next Day, and stay up to date on all of your favorite shows on The HISTORY Channel website at http://history.com/schedule. #AncientAliens Subscribe for more ...

Check out these life altering alien crashes. See more in this Ancient Aliens compilation. Watch all new episodes Fridays 9/8c; Stream Next Day, and stay up to date on all of your favorite shows on The HISTORY Channel website at http://history.com/schedule. #AncientAliens Subscribe for more ...

Countries all over the world are experiencing strange UFO sightings on major mountains. See more in this clip from Season 21, Episode 6, "The Top Ten Mysterious Mountains." Watch all new episodes Fridays 9/8c; Stream Next Day, and stay up to date on all of your favorite shows on The HISTORY ...