Next Episode: www.youtube.com This episode suggests that various sites around the world such Göbekli Tepe in Turkey the Incan ruins of Sacsayhuamán in Peru, the Carnac stones of France, and Zorats Karer in Armenia, show construction techniques and mathematical concepts that were not believed to have been known at the time, and that this knowledge was gained from alien visitors. Next Episode: www.youtube.com ₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪ Playlist: www.youtube.com (Contain all videos for season 2) History Channel -- Ancient Aliens -- Unexplained Structures (Season 2 Episode 8) December 16, 2010 ₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪₪