Some say that ancient coil-shaped artifacts found in Russia’s Ural Mountains may be evidence of a past advanced civilization in this clip from Season 11, Episode 12, "Russia's Secret Files". #AncientAliens Subscribe for more from Ancient Aliens and other great HISTORY shows: ...

Cosmonauts aboard the Russian space station Salyut 7 report having seen creatures reminiscent of angels in space in the past in this clip from Season 11, Episode 12, "Russia's Secret Files". #AncientAliens Subscribe for more from Ancient Aliens and other great HISTORY shows: ...

Some say that the Roswell UFO crash is not the only one to have had witnesses in this clip from Season 11, Episode 13, "Beyond Roswell". #AncientAliens Subscribe for more from Ancient Aliens and other great HISTORY shows: http://histv.co/SubscribeHistoryYT Find out more about the show and watch ...

Roswell researchers suggest that the government sanctioned a bond of secrecy, preventing witnesses of the Roswell UFO crash retrieval from coming forward publicly in this clip from Season 11, Episode 13, "Beyond Roswell". #AncientAliens Subscribe for more from Ancient Aliens and other great ...

Some believe that recently discovered new elements and materials are the result of reverse engineering alien technology in this clip from Season 11, Episode 13, "Beyond Roswell". #AncientAliens Subscribe for more from Ancient Aliens and other great HISTORY shows: ...

People who claim to have been abducted by aliens also say their DNA was manipulated and that human-alien hybrids live among us in this clip from Season 11's episode, "The Returned". #AncientAliens Subscribe for more from Ancient Aliens and other great HISTORY shows: ...