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archaeologicalEcuador· South America-2.8333°, -78.1667°

Tayos Cave

Deep in the Amazon rainforest of Ecuador lies Tayos Cave, one of South America's most enigmatic archaeological mysteries. This sprawling underground network gained international attention when explorer Juan Moricz claimed to have discovered an ancient metal library within its watery depths, sparking decades of speculation about advanced pre-Columbian civilizations. Today, adventure seekers can explore the same chambers that have captivated researchers and treasure hunters for generations.

Cueva de los Tayos is a cave system located on the eastern slopes of the Andes Mountains in Ecuador's Morona-Santiago province. The cave derives its name from the tayos, nocturnal oilbirds that nest within its chambers and in numerous other caves throughout the Andean jungles of South America. The site gained international attention in the 1970s when explorer Juan Moricz claimed to have discovered a "metal library" within its depths, though no scientific expedition has verified the existence of ancient metal plates. Gates investigated the cave's watery passages in search of evidence for this legendary library, diving and exploring deep chambers that have captivated treasure hunters and alternative historians for decades.

Timeline

c. 1500s

Local indigenous peoples known to use the cave for hunting tayos birds

1969

Juan Moricz publicly claims discovery of a metal library within the cave

1976

Joint British-Ecuadorian expedition explores the cave, including astronaut Neil Armstrong

2017

Gates investigates the metal library legend for Expedition Unknown

Gates’ Investigation

  • Gates explored the watery depths of Tayos Cave, diving flooded chambers in search of evidence for the legendary metal library claimed by Juan Moricz
    S04E06
  • The episode examined the claims made by Moricz and later popularized by Erich von Däniken, investigating whether any physical evidence supports the existence of ancient metal plates
    S04E06
  • Gates and his team navigated the cave's challenging underground passages where tayos birds nest in large numbers
    S04E06

What Experts Say

The Cueva de los Tayos legend entered popular culture through the claims of Hungarian-Argentine explorer Juan Moricz, who in 1969 stated he had discovered a vast library of metal plates inscribed with an unknown script deep within the cave. Erich von Däniken later popularized these claims in his books, suggesting the library was evidence of ancient astronauts or a lost advanced civilization. However, mainstream archaeologists have found no credible evidence supporting the existence of such a library, and subsequent expeditions—including a well-documented 1976 joint British-Ecuadorian expedition that included Neil Armstrong—found no metal plates or inscribed artifacts.

The cave itself is scientifically significant for its biological rather than archaeological features. Tayos, or oilbirds (Steatornis caripensis), are nocturnal frugivorous birds that use echolocation to navigate the complete darkness of cave systems. Indigenous groups in the region have traditionally entered the caves to harvest young tayos, valued for their high fat content. The cave's name reflects this long-standing relationship between local peoples and the site, predating the metal library claims by centuries.

Gates' investigation approached the metal library legend with appropriate skepticism, consulting available evidence and exploring the physical challenges of the cave system. The episode acknowledged the site's genuine cultural significance to indigenous communities while examining why Moricz's unverified claims gained such traction in alternative archaeology circles. Without physical evidence or credible documentation supporting the metal library's existence, mainstream scholars view it as a modern legend rather than a legitimate archaeological mystery.

The Tayos Cave case exemplifies a recurring pattern in alternative archaeology: a remote, difficult-to-access location combined with unverifiable claims creates a narrative that persists despite lack of evidence. Gates' approach—physically investigating the site while contextualizing it within both local tradition and the history of the legend itself—demonstrates the difference between curiosity-driven exploration and uncritical acceptance of extraordinary claims.

Fun Facts

The cave is named for tayos birds (oilbirds), nocturnal fruit-eating birds that use echolocation to navigate in complete darkness

Astronaut Neil Armstrong participated in a 1976 British-Ecuadorian expedition to explore Cueva de los Tayos

Indigenous peoples have traditionally harvested young tayos birds from the cave for their high fat content

Numerous caves throughout the Andean jungles of South America serve as homes for tayos bird colonies

Planning a Visit

Getting There

Cueva de los Tayos is located in a remote area of Ecuador's Amazon region and requires significant planning to visit. Access typically involves traveling to the Morona-Santiago province and arranging for local guides familiar with the cave system. The cave's flooded chambers and vertical shafts present serious technical challenges requiring proper equipment and experience.

Nearest City

Macas, capital of Morona-Santiago province, approximately 50-60 kilometers northwest of the cave.

Best Time to Visit

The eastern Andean slopes of Ecuador experience heavy rainfall year-round, though the slightly drier months of October through December may offer better conditions. Cave conditions remain challenging regardless of season, and water levels can vary significantly.

Related Sites

Visitor Highlights

  • Navigate through massive underground chambers and water-filled passages
  • Explore the cave system where the legendary metal library was supposedly found
  • Experience the pristine Amazon rainforest surrounding the cave entrance
  • Learn about the ongoing archaeological debates and scientific investigations

Best time to visit: Visit during Ecuador's dry season from June to September when water levels are lower and cave access is safer.

Travel tip: Hire an experienced local guide and bring waterproof gear, as parts of the cave system require swimming through flooded passages.

Featured In1 episodes

Historical data sourced from Wikipedia