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!

The Carnac Stone are the largest collection of standing stones in the world, but nobody really knows why they were built in this clip from Season 9, "Mysterious Structures". #AncientAliens
Subscribe for more from Ancient Aliens and other great HISTORY shows:
histv.co/SubscribeHistoryYT

Find out more about the show and watch full episodes on our site:
po.st/AncientAliens

Check out exclusive HISTORY content:
History Newsletter: po.st/HistoryNewsletter
Website - po.st/HistoryWeb
Facebook - po.st/HistoryFacebook
Twitter - po.st/HistoryTwitter

HISTORY® is the leading destination for award-winning original series and specials that connect viewers with history in an informative, immersive, and entertaining manner across all platforms. The network’s all-original programming slate features a roster of hit series, premium documentaries, and scripted event programming.

• Ancient Aliens: Carnac Stones Baffle Archaeologists (Season 9) | History ( Download)
• Ancient Aliens: The Impossible Stone Blocks of Puma Punku (Season 9) | History ( Download)
• Ancient Aliens: Mystic Obelisks in Egypt (Season 9) | History ( Download)
• Ancient Aliens: TOP 4 MESMERIZING ALIEN STRUCTURES ( Download)
• Ancient Aliens: Extraterrestrial Bacteria and the Origins of Life (Season 9) | History ( Download)
• Ancient Aliens: The Mars Monolith (Season 9) | History ( Download)
• Ancient Aliens: Sumerian Tablets' Mystic Ancient Messages (Season 9) | History ( Download)
• Ancient Aliens: Indonesia's Lost Pyramids (Season 9) | History ( Download)
• The Stones of Carnac: Who Built These Mysterious Ancient Megaliths ( Download)
• Ancient France - The Carnac Stone Alignments ( Download)
• The Carnac Stones | A Mystery of EPIC Proportions #history #shorts ( Download)
• Ancient Aliens: Egypt's Alien Coffins (Season 12) | Exclusive | History ( Download)
• Little-known curiosities about the Carnac stones! ( Download)
• Mystery of the Carnac Stones + Deformed Planet WASP - 103B DISCOVERED ( Download)
• Carnac Stones of Brittany. Archive film 94430 ( Download)