Ancient Aliens: Season 18, Episode 13

18 - 13: Ancient Aliens On Location: Decoding The Alien Glyphs

Ancient Aliens has examined the oldest and most mysterious rock art on Earth–up close and in person. Now, Giorgio Tsoukalos takes a look back at the incredible hieroglyphs, petroglyphs, and geoglyphs that he believes tell a worldwide story–of alien visitation.