Descending into Ecuador’s Cueva de los Tayos, or Cave of the Oilbirds
Descending into Ecuador’s Cueva de los Tayos, or Cave of the Oilbirds
Descending into Ecuador’s Cueva de los Tayos, or Cave of the Oilbirds (Eoin Carey/Tayos Art)

Journey to the Center of the Earth

For nearly half a century, legends of a giant cave in the Andes—holding artifacts that could rewrite human history—have beckoned adventurers and tantalized fans of the occult. Now the daughter of a legendary explorer is on a new kind of quest: to tell the truth about the cave in order to save it.

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The world’s most mysterious cave is difficult to reach.

To get to Cueva de los Tayos—Cave of the Oilbirds—drive east out of Ecuador’s capital city of Quito for eight hours along narrow, potholed roads that twist through cloudforest above the Amazon Basin. Pull over outside the small town of Mendez, and walk a path to the bank of the muddy Santiago River, where you’ll see locals hauling 150-pound bushels of bananas on their shoulders. Lower yourself into a long wooden canoe and glide past cascading waterfalls to the start of a dirt trail. Hike five hours in the humidity, over Puntilla de Coangos mountain, then up to the summit of Bocana de Coangos. The trail ends at a clearing with three thatch huts, home to a dozen Shuar, the ancient tribe that guards the cave.

The Shuar are the Indigenous people of the region, legendary warriors known for shamanism and for shrinking the heads of their enemies. Tayos beckons from deep inside territory that is managed and protected by the tribe, and visitors must take great care when navigating the local politics and customs. Theo Toulkaridis, a geology professor and researcher at the University of the Armed Forces in Ecuador, who is a leading expert on Tayos, learned this the hard way in 2014. After a few days exploring the cave, he climbed out to find 20 angry Shuar waiting for him. Toulkaridis had hired local guides, but other Shuar were upset that they had not been hired as well. “My guide hugged me close and whispered, ‘Don’t resist,’” Toulkaridis recalls. Then a Shuar woman whipped him with a belt.

Tayos is named for the brown-feathered, hook-billed nocturnal birds that dwell inside the cave alongside thousands of bats. The birds act a lot like bats, spending their days in darkness and heading out at night to forage for fruit. They’re called oilbirds ­because of their fatty chicks, which the Shuar capture and reduce to oil. The cave is also rumored to contain artifacts of a lost civilization. A 1972 bestselling book by Swiss author Erich von Däniken, called The Gold of the Gods, claimed that Tayos held carved passageways and a “metal library” of tablets written in an unknown language. Von Däniken has long believed that aliens once inhabited the earth, and the tablets fit his theory that extraterrestrials helped ancient people evolve. The notion has been criticized as pseudoscientific and racist, attributing the achievements of now marginalized earthlings to ­interlopers from space. Yet it spawned a cottage industry of books, conventions, and TV shows, ­including the History Channel’s Ancient Aliens, which premiered in 2010 and is one of the network’s most popular programs.

A couple of years after The Gold of the Gods was published, the late Scottish explorer Stan Hall assembled a team of 100 scientists, cavers, British and Ecuadorean military personnel, and, remarkably, astronaut Neil Armstrong, who served as a figurehead, and led them into Tayos to unravel the mystery. What they found astonished them. Deep inside, in spots where it would have been impossible to lug machinery, there were stone passageways that appeared to have been cut at right angles and then polished. They also discovered a burial site dating back to 1500 B.C.

“The cadaver, as if surprised by the sudden intrusion after so many lonely centuries, crumbled to dust when touched,” Hall writes in Tayos Gold, his book about the expedition. Though the team didn’t find the metal library, Armstrong put the adventure “up there with the moon landing.”

Beyond that, only a small number of intrepid hikers, wide-eyed UFO believers, and even a team of researchers from Brigham Young University—who believed that the metal tablets might be linked to the Mormon faith—have made it inside. The cave has also attracted interest from geologists and archaeologists, who have mapped portions using 3D technology to better understand its scope. (Roughly four miles of the cave have been mapped so far, but an estimated three miles remain.) Toulkaridis calls it “a natural laboratory which is fundamentally untouched.”

To enter Tayos, you need more than the permission of the Shuar. You also need a blessing from the cave itself. I learn this late one starry night in August of 2019, in Kuankus, the tiny Shuar settlement, which is located about one mile uphill from Tayos. Getting here has been a brutal ten-hour slog in sweltering heat. The trek included crossing a rickety rope bridge high above the rapids and trudging in mud through thick jungle loaded with giant black bullet ants, so named because being bit by one feels like being shot. The plan is to stay in Kuankus for the night, then enter the cave with our Shuar guides the next morning.

I’m here with a small team led by Eileen Hall, Stan Hall’s 34-year-old half-Scottish, half-Ecuadoran daughter, who continued her father’s quest to understand the true history and power of the cave after he died of prostate cancer in 2008. Eileen, who lives in London, is artistic and spiritual, a former architect who now conducts what she calls energy-healing work with private clients. Along with another architect, Tamsin Cunningham, she is also a cofounder of Tayos, a company that explores the cave through writing, music, and meditation. Today, with her long brown hair in a ponytail, she’s dressed in a black Ecuadorean shirt, long gray hiking pants, and blue rubber boots caked in mud. This is her fourth expedition to the cave. When I ask her what I should expect, she tells me that Tayos is “a psychedelic experience.”

After sipping from a wooden bowl of chicha, a chalky, alcoholic drink made from fermented yuca (prepared by women who chew it and then spit into the bowl), we gather with the Shuar around a campfire. A shaman—a stout, middle-aged woman with long, dark hair—leads us through the permission ceremony. We hold hands while in Spanish she thanks the stars, the moon, the earth. She removes a smoldering log from the fire, waving its smoke behind each of us in a blessing. Finally, we take turns asking for permission from Arutam, the all-powerful force in the Shuar religion, to enter Tayos. After a few moments of silence, the shaman tells us that the spirit has allowed us inside what she calls “the womb of the earth.”

Shuar guide Jaime Tiwiram giving a blessing before leading a group into the cave
Shuar guide Jaime Tiwiram giving a blessing before leading a group into the cave (Eoin Carey/Tayos Art)
Stan Hall, 1975
Stan Hall, 1975 (Tayos Archives)
The Coangas River
The Coangas River (Eoin Carey/Tayos Art)
The 1976 expedition
The 1976 expedition (Tayos Archives)

“Morder la cabeza”—bite off the head—the street vendor says as he hands me a chontacuro, a plump white grubworm fresh from a sizzling grill. As I struggle to distinguish the head from the body, Eileen says, in her Scottish brogue, “It’s that little black thing right there.”

It’s a few days before our descent into Tayos, and we’ve stopped for a break in Mera, a small gateway town to the Andes. A band plays drums and trumpets just off the town square where local merchants sell crafts and food. Eileen sways to the festive music and compliments a local craftswoman on her butterfly earrings. Though Eileen has been living in the UK since she was a young girl, she was born in Ecuador and feels deeply connected to the country. If it wasn’t for Tayos, which drew her father here decades before, she wouldn’t even exist.

Eileen’s father never dreamed of becoming a famous explorer. As a young married man in Dunbar, a seaside town near Edinburgh, he was a mild-mannered civil engineer with a bookish interest in science, history, and travel. “He got interested in explorers,” ­Eileen says. “People like Lawrence of Arabia who would go off into the unknown.” Reading about Tayos in The Gold of the Gods captured his imagination like nothing before. Von Däniken claimed that an Argentine-Hungarian explorer, Juan Moricz, had taken him to the cave, where they found the tablets that, he wrote, “might contain a synopsis of the history of humanity, as well as an account of the origin of mankind on earth and information of a vanished civilization.”

The fantastical account gripped Hall, who on a whim decided to write to Neil Armstrong and invite him to take a trip to the cave in 1976. Armstrong, recently world-famous from his moon walk, could draw enormous attention to the venture, and as Hall had learned, the astronaut had Scottish roots, so he just might consider the idea. To Hall’s shock, Armstrong wrote back saying he was interested. With that letter in hand, Hall approached both the British and Ecuadorean governments, which agreed to provide funding and helicopter transportation to the site. Within a year, Hall had organized one of the largest cave expeditions of his time.

Stan Hall assembled a team of scientists, cavers, military personnel, and, remarkably, astronaut Neil Armstrong, and led them into Tayos.

Hall’s journey made him famous, inspiring him to quit his day job and move to ­Ecuador to keep exploring the cave. But it also ended his first marriage, which couldn’t endure the strain. In Quito, he met and married an Ecuadoran woman, Janeth Muñoz, who shared his passion for Ecuador’s history, and in 1986 she gave birth to their daughter. For Eileen, growing up as the child of a celebrated explorer felt like a fairy tale. But Muñoz, who still lives near Edinburgh, says that Hall struggled to get support for his research. He was consumed by his search for the legendary library, and the only money they had came from his occasional consulting jobs. When he wasn’t strategizing with treasure hunters over beers, he was off with the Shuar, who made him a blood brother of the tribe. “Dad became obsessed, he called it the fever,” Eileen recalls. With Hall so caught up in his work while Ecuador was on the verge of a deep financial crisis, they were often unable to pay their rent.

Hall and Muñoz had a second daughter, and in the mid-1990s Muñoz insisted on moving the family to Scotland to have a safer and more stable existence. For ten-year-old Eileen, the relocation—in the middle of the Scottish winter—was devastating. She was the only brown-skinned, Spanish-speaking child in her class. Bullied by other students, she became depressed and at times suicidal.

As she matured into adulthood, Eileen took steps to find meaning in her life. She traveled around Europe and earned a degree in architecture. Meanwhile, her father continued to return to Ecuador, where his fruitless searches for the metal library grew increasingly frustrating. He was also, Eileen learned, dying of cancer.

Late one night in 2008, while holding vigil at his bedside in Scotland, she was struck with a new sense of purpose: she would keep his work alive. For her, Tayos was about more than the mysteries of the Shuar—it was also a connection to her origins. She would go back to Ecuador, she promised him, and continue the journey he had begun. “I’m going to follow your spirit,” she said just before he died.

Eileen’s decision left her mother with mixed emotions. “I feel proud of her,” Muñoz says, “but I suppose she is going to encounter the same kind of problems that he did,” with trying to protect the cave.

Eileen Hall in her London flat
Eileen Hall in her London flat (Juliette Cassidy)
Eileen Hall’s 2018 expedition
Eileen Hall’s 2018 expedition (Eoin Carey/Tayos Art)
An oilbird
An oilbird (Tayos Archives)
Neil Armstrong inside Tayos in 1976
Neil Armstrong inside Tayos in 1976 (Tayos Archives)

After 2010, the Shuar began guiding small groups of tourists into Tayos. Then, in 2015, Eileen made her first trip into the cave with an Ecuadoran documentary filmmaker. She was excited, but the realities of the journey felt treacherous. It was the rainy season, which meant flooding streams and water coursing down muddy slopes along the approach hike. Entering Tayos begins with a rappel along a series of ropes, and on the descent Eileen was frightened by the screaming oilbirds lurking in the blackness. Once on the ground, she found the cave so overwhelmingly dusty and dark that she jumped at the first chance to leave before nightfall. “It was all too much,” she says.

Two years later, in 2017, she was invited to return for an episode of Expedition Unknown, a Travel Channel program. Though she had grown up with what she calls “the treasure story” of Tayos, she was no longer convinced that a metal library existed, and even if it did, she didn’t think it would be the work of little green men. Now she felt like a prop in an overwrought reality show. She couldn’t stomach the host’s perfunctory treatment of the Shuar and his blustery mugging for the camera: as he entered one shadowy chamber, he proclaimed, “This just got real!”

Eileen felt a growing sense of alienation in a male-dominated adventure narrative. Explorer stories—from Columbus to Shackleton to Neil Armstrong—are predominantly about white men seeking the edges of the known world. Where did she fit in? “Men went off and discovered new lands, and that’s why our history is that women have to stay at home,” she told me. “For me this journey has been about finding my voice as a woman.”

In August 2018, she led her first expedition to Tayos, a trip with both artistic and scientific goals. She didn’t want to just investigate the cave; she wanted to find new ways of experiencing it. To do this, she brought along a small group of artists, including Jon Hopkins, an electronic musician from England, and neuroscientist ­Mendel Kaelen, who would measure how listening to music in the cave impacted the brain.

Once inside, Eileen and the artists made their way into the shadows, meditating, playing music, and listening to ways that the cave walls sculpted the sound. “It was a gentler way of exploring, instead of this gung-ho way,” she says.

She emerged four days later with a new sense of the place, and of herself. “In shamanic work, you go into the darkness and the shadow, but the moment you run away from it is when you get into trouble,” she says. “For me the cave is this idea of facing the unknown and befriending it to receive a more complete wisdom about life.”

Hall’s Tayos team inside the main chamber
Hall’s Tayos team inside the main chamber (Eoin Carey/Tayos Art)

For our trip, Eileen had a vision, a project that would bring together creativity and activism. The plan is to record musical performances inside the cave for a multimedia installa­tion in London. Publicity from that will generate support for Unesco World Heritage site designation, protecting the area around Tayos from mining and other threats. The musicians are an Ecuadoran multi-­instrumentalist named David Villa­gomez and British producer Henry “Hoffy” Hoffman. We’ll set up camp an hour’s hike into the cave and spend two days and nights there, recording and exploring under the guidance of the Shuar.

Eileen admits that skeptics would probably label her New Agey, but Toulkaridis told me that, after initially being resistant to her idea of playing music in the cave, he has no objections to the esoteric nature of the enterprise. To him, anything that helps spread the word about the fragility of the region’s landscape and the Shuar people is worthwhile. “Scientists have no outreach to the mass media,” he says. “You need someone who can help get the message heard.”

A seminomadic, polygynous tribe spread across the forests of Ecuador and Peru, the Shuar have been fighting against colonization and missionization since the Spaniards invaded their territory in the 16th century. To the Europeans, they were subjects of fascination: a warrior culture known for shrinking the heads of their victims as a way of capturing souls. In battle they believed that their shaman could conjure invisible darts to destroy their foes. They were so feared that in 1995 the Ecuadorean army developed elite units of Shuar soldiers for territorial battles with Peru.

Since the 1960s, the Shuar have maintained jurisdiction over portions of their land, and they’ve become a powerful force in protecting the country’s natural resources. In 2008, they helped persuade the Ecuadorean legislature to pass the world’s first law granting the kinds of legal rights to forests and rivers that are ordinarily reserved for people.

Still, the Shuar are vulnerable to development. In 2012, the government entered into a contract with Ecuacorriente S.A. in which the Chinese-owned mining company would invest $1.4 billion to build a copper and gold mine in the heart of Shuar territory. The move defied Ecuadorean law and international agreements on the rights of Indigenous people, according to the ­International Federation of Human Rights and the United Nations. Called the Mirador Mine, it’s the first large-scale mining operation in the country and will occupy some 22,000 acres of forest. Since construction began, the Shuar have staged numerous protests. There have been violent confrontations with police and military forces, and at least two anti-mining activists have been murdered.

Eileen told me that her father earned the respect of the Shuar and that the tribe was instrumental in helping him gain access to the cave. “They were very welcoming,” she says. After three past trips to Tayos, she’s developed her own familial connection with Kuankus villagers, who dress in modern clothing but still mostly live off the land. When we first arrived, a middle-aged Shuar woman named Susana Wamputsar and her husband, Don Bosco Tiwiram, presented ­Eileen with handmade jewelry.

After the ceremony giving us permission to enter the cave, we sit with the couple—along with one of their sons, Jaime, who will be our primary guide and translator—on a small wooden bench outside a thatch hut. As Susana speaks, Jaime translates her words into Spanish, then Eileen translates them into English so I can follow along. Susana, who was around 12 when Hall’s expedition came through the area, recalls the dramatic sight of the helicopters landing. She says the elders in her community wouldn’t dare go near the cave while the foreigners were there. According to folklore, the men left with “a thigh bone,” she says, as well as boxes of ceramics. She recounts another well-known story, about a time decades earlier when an Italian monk named Father Carlos Crespi left the cave with “tablets wrapped in newspaper.”

After a few moments of silence, the shaman tells us that the spirit has allowed us inside what she calls “the womb of the earth.”

Ecuador banned expeditions to Tayos soon after Hall’s expedition, so that the Shuar could “come back to their place and just be with the cave,” Susana explains. It remained closed to foreigners until the Shuar began offering tours a decade ago. When I ask her what the Shuar believe is inside Tayos, she tells me that there is a tall stone that contains salt, as well as a “double spirit.” One is Nunkui, a female entity who protects and cultivates the plants of the area. The other is Weh, who makes healing salts. For centuries, the Shuar would descend into Tayos to retrieve Weh’s magic salts. But since others began traipsing through the cave, says Jaime, Weh has receded into the shadows. Now he believes Weh is ready to return. Earlier in the year, Jaime was in the cave with a group of tourists when he heard a loud noise coming from a high cranny of a cavern. “It sounded like footsteps,” he says.

Jaime, who is intense and wiry, with thick black hair and bangs, flipped on his ­headlamp and, along with another guide, shimmied over fallen rocks toward the sound. At a narrow passageway, the footsteps grew louder and louder, spooking the other guide so much that he retreated, but Jaime crawled inside. He was alone when everything suddenly went silent. Then he looked down and saw a giant footprint.

“A footprint?” I ask, skeptical.

“I have a picture,” he replies, matter-of-factly. He swipes at his phone, then hands it to me. The photo indeed shows a fat, wide footprint in brown mud that, by my count, has seven toes.

His account would feel like a hoax if Jaime wasn’t so stoic and his words weren’t so heartfelt. The Shuar consider dreams to be visions, and for weeks, Jaime says, he has been seeing Weh in his sleep. The spirit, appearing in the form of a Shuar man, told Jaime that he wants to return.

Jaime says he also had been having dreams of Eileen coming back to Tayos, bringing others with her. Together with Jaime, they would sit deep inside the cave in total silence, and if they waited long enough, Weh would emerge. Turning to Eileen, Jaime tells her that, physically, she may live in London, but her true spirit is in Tayos. “I feel that you live in the cave,” he says.

Oh, and the group from his dreams who would conjure Weh with her? That would be us.

This just got real!

The mouth of Tayos opens at the end of a steep path in the rainforest. As we walk toward it on the morning of our descent, butterflies flutter between the leaves. A four-inch caterpillar, with black and yellow stripes and spiky green hairs, navigates a sodden log. There are also things that look like aliens. Near the entrance of the cave, we see a triangular gray rock that resembles the head of an ET, with impressions for eyes. Then there’s the entrance itself, which looks a lot like the outline of an extraterrestrial’s face. Perhaps the psychedelic experience Eileen spoke of begins here.

One by one, we take turns stepping down toward the mouth and slipping into our harnesses, while Jaime and a half-dozen other Shuar connect rappelling devices to ropes secured to the side of the entrance. The 200-foot descent along jagged wet shale lasts about five minutes but feels like an eternity, and I sense that I’m entering another world. About midway down, with the sunlight receding, I hear, for the first time, the distant screams of the cave’s namesake birds. And by screams I mean screams: like Linda-Blair-with-her-head-backwards-in-The-Exorcist screams. Capable of hitting 100 decibels—greater than a snowmobile engine—they are among the loudest birds on the planet. When they’re not screaming, they’re clicking, using echolocation to navigate the darkness. They spend their days perched on rock shelves throughout the cave, heading out at night to forage.

Once inside Tayos, it’s difficult to get a true sense of scale. For the most part, this isn’t a claustrophobic maze of narrow passageways; it’s a series of massive chambers, some hundreds of feet tall.

With our headlamps illuminating the darkness, we clamber away from the entrance over several dozen yards of massive fallen boulders, then rappel down a 15-foot precipice. This takes us to a famous landmark, the Juan Moricz arch, named after the explorer who purportedly led Von Däniken into the cave. Separating two chambers, it appears to have been precisely cut and smoothed. In The Gold of the Gods, Von Däniken writes: “I’d like to see the archaeologist with the nerve to tell me that this work was done with hand-axes!”

He should talk to Florencio Delgado, an archaeologist at San Francisco de Quito University who has studied the cave during multiple visits. “It’s a made-up story,” he says. Toulkaridis, the geologist, agrees. “I call myself the assassin of ignorance,” he tells me with a laugh. The cave is something like 25,000 to 30,000 years old, he says, and is composed of sandstone and carbonate. The polished walls were created by geodynamic pressure grinding the rock into layers, which were then carved by the water that flowed around them.

The deeper we go into Tayos, the more spectacular it becomes. We step into a giant cavern, which I nickname King Kong’s Palace. Boulders cover the ground like fallen ruins, and the cave’s ceiling looms at least a couple hundred feet overhead. In the distance, there’s another passageway with perfectly smooth walls that rise and meet at close to a right angle.

Around the corner, we come to the gargantuan Main Chamber. It could hold a 20-story building lying on its side, and it’s just as tall. The light from our headlamps fades before it reaches the far side. The ground is rocky, lunar, and black, but unlike the moon it’s teeming with life. Giant brown tarantulas stroll between stones. I catch the glimmer of the silvery back of a three-inch beetle before it scurries into the shadows. On a small boulder, we spy what looks like a steampunk insect, part flesh, part machine. It’s an Amblypygi, or whip spider, and as we get closer, we see that it has a beetle in its mandibles.

After pitching our tents and filling up on lentils and rice, we fall asleep to the cries of the oilbirds, which gradually fade to silence.

The 2018 expedition
The 2018 expedition (Eoin Carey/Tayos Art)
The author in the Altar of Light chamber
The author in the Altar of Light chamber (Courtesy David Kushner)
Ecuadoran musician David Villagomez
Ecuadoran musician David Villagomez (Eoin Carey/Tayos Art)

The only way to tell that it’s morning in Tayos is by the Altar of Light. Located at the far end of our encampment, the towering chamber is the one spot other than the entrance where sunlight makes it inside. The light streams in through two openings some 200 feet above, along with a shower of rain. Shoots of tall green grass rise from the mound of rich black soil below.

It’s a remarkable setting, and Eileen and the musicians decide to do some recording. Hoffy sets up his equipment, while Villagomez perches on a rock with his flute. But then something overcomes Villagomez, who bursts into tears. Until now he’s been a jovial, good-humored part of the troupe, but he’s sobbing heavily. When he recovers some 15 minutes later, after being comforted by the group, I ask him what happened. He cites the overwhelming energy in the Altar of Light chamber and says, “I felt something inside me die.” That sounds far-out, but in this spot it’s understandable, and it’s hard not to be moved when Villagomez begins to play.

After the session, we take turns standing in the rays of sunlight slashing down to the chamber floor. As the sun arcs higher, they slowly merge into a single beam, shooting down between two towering pillars of rock. If this was an Indiana Jones movie, the light would be pointing to some secret burial site—which, actually, it might have been.

As Stan Hall claims in Tayos Gold: “20th July 1976, 11:25 A.M., seven years to the day since Neil Armstrong’s left foot made that ‘first small step for man’ on the Moon,” a scientist on Hall’s team “was kneeling on a pile of guano molesting a scuttling beetle with a twig when he scraped across a shard of pottery.” The shard led to others, and eventually a cadaver. The location: the spot where the light points when it splits the rocks.

“I’m 100 percent sure that if rituals have been done, they’ve been done there,” Toulkaridis tells me. “The Indigenous people before the Shuar wouldn’t care about flat surfaces but about how the sun shines inside that area.”

That afternoon, Jaime guides us deeper into the cave. The terrain transforms from large caverns to smaller passageways, and we shimmy and bend around sharp stalactites. Eventually, we come to an area where the ceiling is only about five feet off the ground, a spot that Jaime says is dark and still enough for Weh. We shut off our headlamps and wait in silence. The only sound I hear is a bat’s flapping wings, which sends an occasional breeze at my face. After 20 minutes or so, Jaime announces that he feels the presence of a being. Hoffman tentatively asks, “Which being is it? Is it, um, the one with salt?”

In fact, Jaime says it’s another one, a guardian who’s watching out for the cave, and for us. According to Jaime, the spirit is saying, “This is a very sacred place, very few people have been through here.” The spirit says we shouldn’t have used the complicated route through the stalactites, and that we should go around them on the way out. The spirit of Stan Hall is with us, too. “I can feel it,” Jaime says.

The group is quiet for a beat. The others say they don’t sense anything. I say I felt only a cold breeze that blew for a few seconds. A change in temperature, Jaime notes, is what happens when a spirit comes and goes.

Our journey inside Tayos culminates at a crystal-clear waterfall pouring over a 15-foot rock wall into a shallow pool. After our trek through the jungle and two days in the cave, it’s a welcome shower that we savor before heading back to our camp.

That wouldn’t be our last opportunity to get wet. When we wake up the next morning, rain is pouring into the Altar of Light. By the time we pack our gear and make it past the Juan Moricz arch, the water is pouring over the walls and rising at our feet, drowning out our voices and forcing us to shout. It’s a harrowing moment, especially when Jaime and the other Shuar disappear inexplicably into the shadows before suddenly emerging to help us make our exit.

One by one, we pull ourselves up against the current and over a small wall, but the downpour into the mouth of the cave is so intense that ascending the ropes is impossible. If it doesn’t let up, we’ll have to camp another night, then try again tomorrow. After a couple of hours, though, the rain settles and we begin our climb. The Shuar outside the cave yank us up in fits and starts, which sends me hurtling into the wall. Emerging from the mouth into the misty daylight has me thinking that Eileen was right after all: spending three days inside this mystical underworld was a total trip.

“For me the cave is this idea of facing the unknown,” Eileen Hall says, “and befriending it to receive a more complete wisdom about life.”

As a new generation seeks out Tayos, the elder Western mythmakers of the cave are losing their hold on the legend. Last spring I drove past the golf courses and palm trees of Indian Wells, California, to watch Erich von Däniken, now gray haired and hard of hearing, address his minions at Contact in the Desert, one of the largest UFO conventions in the world. Hundreds of fans in alien T-shirts and glow-stick hats packed the hall to hear his revisionist history of how, among other things, the biblical Abraham “was on a spaceship in orbit.”

When I speak with him afterward, Von Däniken is greatly interested to hear that Stan Hall’s daughter is continuing to explore Tayos. But he admits that he’s no longer certain aliens visited the cave. Now he has a new theory: “I think a metallic library does exist,” he says, “but it belongs to the Mormons.”

Back in Ecuador, Eileen reflects on our journey over a lunch of chicken and rice. The trip has deepened her resolve to tell a new chapter of Tayos to the world, she says. She’s eager to craft the multimedia installation in London and online. (The installation would be delayed indefinitely by the coronavirus pandemic, but the digital version, called the Liminal Compass, was set to launch this fall at, where she was accepting donations for the project.) When international travel is viable again, she hopes to partner with big-mountain skier turned mindset coach Kristen Ulmer to lead a workshop in which participants will “face their fears” inside the cave. And she and Toulkaridis are planning another expedition to conduct further research as part of their campaign to convince Unesco to protect the site.

“Every time I come back,” she says, “there’s a deeper connection with the Shuar, with the space, and with the story.”