This episode explores the recurring keyhole shape found in ancient monuments, sacred texts, and artwork across unrelated cultures, asking whether it represents a message left by extraterrestrial visitors. The investigation begins when Cydonia Institute researcher George Haas identifies a symmetrical keyhole-shaped formation on Mars in 2013 imagery from the Mars Reconnaissance Orbiter, prompting ancient astronaut theorists to compare it with earthly structures. The most striking example is Japan's Daisen Kofun in Sakai, a fifth-century megalithic tomb stretching 1,600 feet long and covering five million square acres, encircled by three moats—one of over 160,000 similar kofun tombs built across Japan between 300 and 600 AD. Giorgio Tsoukalos, David Childress, and Andrew Collins suggest the keyhole's global recurrence and aerial-only visibility indicate a deliberate extraterrestrial communication, with the shape appearing in contexts from the Seal of Solomon to structures whose form can only be appreciated from above.
Mainstream archaeology attributes the kofun tombs to Japan's Kofun period emperors and nobility, viewing the keyhole shape as an evolution of earlier round burial mounds combined with rectangular ceremonial spaces for rituals honoring the dead—a design reflecting indigenous religious beliefs rather than aerial blueprints. The Martian formation, while symmetrical, exhibits geological features consistent with natural mesa formations common on Mars. Still, the episode raises genuinely intriguing questions about why ancient builders invested enormous resources in shapes imperceptible from ground level, and whether pattern recognition across cultures reveals universal human symbolism or something more enigmatic—making it worthwhile viewing for anyone curious about archaeological mysteries and cross-cultural connections.
Ajanta Caves
India · Hindu / Buddhist / Jain
Ancient astronaut theorists argue the precision rock-cutting of the Ajanta caves, their deliberate celestial orientations, and their depictions of half-human hybrid beings suggest construction with advanced alien technology and commemorate contact with extraterrestrial visitors. Mainstream archaeologists attribute the caves to devoted Buddhist monks who carved them from the cliff face beginning around 200 B.C., with the celestial alignments reflecting sophisticated but human astronomical knowledge.
Daisen Kofun
Japan · Japanese
Theorists argue that the keyhole shape of the Daisen Kofun and over 160,000 similar kofun tombs across Japan—visible only from the sky—were designed to be identified by extraterrestrials, possibly marking the burial sites of their own ancestors who intermingled with Japan's imperial lineage. Mainstream archaeology identifies the Daisen Kofun as the mausoleum of Emperor Nintoku, the largest tomb by area in the world, built during the Kofun period as a statement of imperial power.
Keyhole stone structures near Khaybar
Saudi Arabia · Ancient Near Eastern
Theorists argue that 19 keyhole-shaped stone enclosures discovered during an aerial survey, dating to roughly 6500 BC, represent a sacred symbol linking heaven and earth and may be connected to keyhole structures built by other cultures around the world. Mainstream archaeologists have not determined who built them or their purpose, though scientific dating places their construction around 6500 BC.
Rennes-le-Château
France · Western Europe
Theorists point to the presence of a statue of Ashmedai, the king of the jinn said to have helped Solomon build his temple, at the former Templar stronghold of Rennes-le-Château as evidence that the Knights Templar sought to communicate with this entity and recover its alien technology. Mainstream historians note the site's fame derives largely from 20th-century esoteric and conspiracy literature rather than documented Templar activity.
Well of Badlapur
India · Ancient Indian / Indus Valley
Theorists argue the well's keyhole shape, mortar-free construction, and symbolic connection to the 18-year lunar cycle mirror the Well of Santa Cristina in Sardinia so closely that both must have been built with guidance from the same extraterrestrial visitors. Mainstream archaeologists date the Badlapur well to around 1715 AD during the time of Shivaji, though locals believe it is far older.