If ancient aliens visited Earth, what was their legacy, and did they leave behind clues that exist in plain sight such as sophisticated aircraft, complex electrical grids, and intricate construction machinery? See more in Season 1, Episode 1, "The Evidence." Watch all new episodes of Ancient ...

Ancient astronaut theorists claim that several UFO-related incidents in China over the years have led to the Chinese government's beginning to acknowledge that extraterrestrial life may exist in this clip from Season 11, Episode 9, "The Hidden Empire".#AncientAliens Subscribe for more from ...

Ancient astronaut theorists believe that the approximately 12,000-year-old Gobekli Tepe monument in modern-day Turkey may have been built by the survivors of a lost society in this clip from Seaspn 10, Episode 2, "Aliens B.C". #AncientAliens Subscribe for more from Ancient Aliens and other great ...

Tune in to Alien Invasion Week on History starting Monday 9/30 through Friday 10/4 for new Ancient Aliens, plus the premiere of In Search Of, new UFO Specials and More! There are quartz obelisks in Egypt that some Ancient Astronaut Theorists believe were used to transmit energy over vast ...

The search continues with new episodes of In Search Of Fridays at 10/9c! Some Ancient Astronaut Theorists believe alien life could be found deep within the earth's most mysterious caves in this clip from Season 9, "Forbidden Caves". #AncientAliens Subscribe for more from Ancient Aliens and other ...