The Journey Of The Kon-Tiki

It is a dangerous experiment. In 1947, natural scientist Thor Heyerdahl (above) and five companions set sail from Peru on a wooden raft. Their destination: Polynesia, some 7,000 kilometres away. Heyerdahl wants to prove that the island world in the Pacific was originally settled from South America. Experts ridicule the Norwegian. Recent genetic analyses, however, have shone a new light on the adventure. 

Within minutes, the calm waters of the Pacific Ocean around the Kon-Tiki have turned into a stormy sea: dark clouds chase across the sky. Powerful waves lift the raft by five or six metres, then abruptly send it plummeting into deep, blue-black valleys. It lurches in the wind. And the logs from which the raft is built move against each other.

Thor Heyerdahl, the 32-year-old Norwegian leader of the expedition, clings to the bow in the rigging, when suddenly a cry for help cuts through the roar of the storm. A crew member has slipped from the raft. The man is drifting in the waves, trying to hold on to the rudder blade—in vain.

Heyderdahl yells commands, but no one hears him amid the roar. One crew member tries to throw a lifeline, but it’s caught in its drum. Another hurls the life jacket into the storm; the wind tosses it back onto the deck. The man in distress is barely visible among the waves. The crew cannot turn the vessel; even tacking against the wind is out of the question. Finally, another crew member jumps into the ocean. He crawls through the waves with one arm, holding a life jacket in the other arm, which is moored to the raft by a line.

Twenty metres from the raft, the two men come together between the waves. The crew hastily pulls them back on board using the line. But the force of the storm is still increasing. Seven-metre-high waves roll beneath the Kon-Tiki. Often, the helmsman at the stern is submerged up to his stomach. For a moment, the raft seems to pause, then the salt water runs off between the logs. And the Kon-Tiki pops up like a cork. 

The six men desperately hold on to everything there is. They attach a board to the steering post so that their helmsman can stand securely. The deck has long since been covered with slippery algae. In the storm, the ropes that sit in deep notches around the nine balsa wood trunks loosen. Finally, the rudder snaps off, and a gust shreds the sail.

Natural scientist Thor Heyerdahl

It is 21 July 1947, and the crew has been sailing across the Pacific for seven weeks. On a raft built according to ancient South American tradition, Thor Heyerdahl and five companions want to make the approximately 7000-kilometre sea journey from Peru to the Polynesian Tuámotu archipelago; but exactly where they will end up, the men do not know. The journey is intended to solve one of the great mysteries of the migrations: Where did the Polynesians come from?

No island kingdom lies as far away from all continents as the Polynesian islets. People have lived on them for centuries. Around 1940, most scholars assumed that they came from Asia. Heyerdahl, on the other hand, believes that indigenous people from South America conquered the distant island kingdom around 500 CE—with rafts made of lightweight balsa wood. His thesis is so daring that no one supports it: never, according to unanimous research opinion, did a raft reach a South Sea coast from South America. No one believed that his crew would even make it to the open sea with the Kon-Tiki. The raft consists of just nine balsa wood logs, moored together by sisal ropes and crossbeams. Only a hut made of bamboo canes provides the crew with protection from the elements.

The story of the Kon-Tiki begins 10 years earlier on the Polynesian island of Fatu Hiva. The young zoologist and geographer Thor Heyerdahl is commissioned by the University of Oslo to investigate how animals have spread from island to island on the wind and the currents. The Norwegian captures countless beetles and fish, identifies species and studies their populations.

One day, in the rainforest of Fatu Hiva, the researcher comes across chunky stone sculptures: creatures with grimacing faces and oversized eyes. They resemble motifs on Peruvian wall reliefs that he had seen on earlier geographical excursions in South America. A little later, Heyerdahl meets a local who tells him about an old legend: “Once we lived in a great land far beyond the sea,” reports Tei Tetua, the last descendant of a tribe that ruled the east coast of Fatu Hiva for generations. 

The old man points to the east, to South America. It was Tiki—the divine ancestor—who led the forefathers to the islands. Heyerdahl is bemused: How should it have been possible that the indigenous people of today’s Peru or Ecuador reached the islands? Then, on the beach, he observes how the waves roll in from the east with the trade wind. Since time immemorial, he notes in his diary, wind and clouds have moved across the Pacific islands from the direction of South America: a phenomenon that also determines the settlement of animals and plants on the islets. Life, he concludes, had spread to the islands from the east.

When he returns to Norway in 1938, he begins to search for circumstantial evidence that could prove early contact between the peoples of South America and Polynesia. Little by little he comes across astonishing similarities, and finally even a trace of that Polynesian patron god Tiki, of whom the native on Fatu Hiva had told him.

Virakocha, the Inca sun god, according to a work on South American mythology, was probably originally called ‘Kon-Tiki’ or ‘Sun-Tiki’. According to a legend, he once sailed west, in the direction of Polynesia. Are ‘Tiki’ and ‘Kon-Tiki’ possibly identical? Did ancestors of the Incas reach the Pacific Islands from today’s Peru or Ecuador?

Wind and current drive the Kon-Tiki across the sea. Manoeuvring is only possible to a very limited extent. Thor Heyerdahl, 32, leads the expedition

Heyerdahl studies ancient sea routes and examines the winds and ocean currents between Polynesia and South America on nautical charts. He knows that many peoples of South America once made their rafts from the wood of balsa trees they cut in the coastal rainforests in what is now Ecuador. The Norwegian estimates their sailing and manoeuvring skills to be superior. He dates the settlement of Polynesia to about 500 CE. At that time, according to archaeologists’ findings, the coastal peoples of Peru and Ecuador had solid rafts.

But hardly anyone is interested in Heyderdahl’s theses. No publisher wants to publish his work. Scientists reject him. The indigenous peoples of South America, they say, had no sea-going ships. They could never have reached Polynesia. A scholar smugly suggests to him: “You could try to travel from Peru to the South Sea Islands on a balsa wood raft.” 

A raft trip with millennia-old technology: an incalculable risk. But at the same time a new way of scientific methodology. Never before has an archaeologist measured a thesis against its feasibility in such a spectacular way.

In the summer of 1946, he meets the Norwegian engineer Herman Watzinger at the Explorers Club in New York: Watzinger spontaneously wants to go along. A financier offers to support the trip. In a few months, Heyerdahl puts together a crew. He does without experienced seamen: no one should be able to accuse him that his men were able to sail and navigate better than the early sailors. Besides, he thinks, sailors do not understand more about rafting than inexperienced explorers. Instead, he invites Norwegian friends: in addition to Watzinger, the painter Erik Hesselberg and radio operators Knut Haugland and Torstein Raaby, who are to radio weather reports at sea to meteorological stations in Lima and send SOS in an emergency. They are later joined by Swedish ethnologist Bengt Danielsson.

Heyerdahl talks to the US Army and touts his trip as an endurance test for new types of equipment. He receives waterproof sleeping bags, matches that burn even when wet, the latest stoves and sunscreen, a special power food in handy packs, rubber bags, special shoes and 684 cans of pineapple.

A British medical officer gives him a ‘shark powder’: sprinkling a few crumbs in the sea is supposed to make the predators disappear. Then the adventurer travels with one of his companions to Ecuador, where the balsa trees grow in the forests of the coastal region. In the jungle, they cut down twelve large trees. They tie their trunks together with lianas to form two rafts and float down a river to the Pacific Ocean. From there, a ship pulls them to Peru.

The crew of the Kon-Tiki (from left): Knut Haugland, Bengt Danielsson, Thor Heyerdahl, Erik Hesselberg, Torstein Raaby and Herman Watzinger. Also on board is a parrot.

In spring 1947, they set about building the Kon-Tiki near the capital Lima. Together with 20 marines, the men hew the balsa logs. They place the largest log, 14 metres long, in the middle. On either side, they symmetrically lay shorter and shorter poles so that the bow is shaped like a blunt plough. Finally, they tighten 300 ropes made of sisal in notches and knot them together. 

They base their work on construction sketches of ancient watercraft once copied by European explorers. But also on the findings of archaeologists who found tiny miniature rafts in 1500-year-old South American desert tombs: their small trunks are knotted with hemp ropes or strips of seal skin. The models show how the trunks were shaped at the bow and stern to reduce water resistance. A rectangular reed sail still hangs from one mast—Heyerdahl had a similar one made from linen cloth for his raft. 

Between the trunks of their Kon-Tiki, the men insert five two-metre-long pine boards: they are to serve as keels and prevent the raft from drifting with the wind. At right angles to the trunks, they lay additional beams at intervals of one metre. On top of this they put a sturdy lattice of bamboo poles, which serves them as a deck. They cover this grid with mats of woven bamboo straw, on which they will sleep, walk and live. Later, the crew will stow the boxes of provisions in the cavities created underneath.

On the deck, the men erect a hut as a sleeping den, and in front of it a mast made of mangrove wood. It consists of two poles moored together and carries a cross beam, a yardarm, to which they attach the sail. They fix a board to the top of the mast to serve as a lookout. In addition, a second, smaller sail can be rigged there. 

As closely as they follow records and lore, not all questions can be answered before the trip: did the indigenous people impregnate their rafts, for example with solutions of resin, wax or rubber? How often were the logs detached again and brought ashore to dry out in the sun? 

The expedition could cost them their lives, a fact of which Heyerdahl is becoming increasingly aware. The radio could fail; the dinghy, an inflatable boat, is neither seaworthy, nor can it accommodate all six men. And whether a ship will rescue the crew in an emergency, no one knows.

On 27 April 1947, the raft is christened after the Inca sun god. The next day, the fragile vessel sets sail. The Kon-Tiki is loaded with 1,041 litres of water in 56 jugs, bananas, sweet potatoes, bottle gourds and 200 coconuts. Each man owns a private box. Two boxes hold sextants and anemometers and a 16-millimetre camera along with rolls of film.

The men push cardboard boxes into steerage that they have previously sealed water-tight with a sticky layer of tar and sand. They store four months’ worth of military rations inside: Heyerdahl estimates that they will have to sail at least 97 days to the Tuámotu archipelago—if the wind keeps them going. 

The raft being built at a shipyard in Peru. Heyerdahl and his companions based it on sketches of old watercraft copied by European explorers. 300 ropes made of sisal hold the raft together.

Around 4.30 p.m., a tugboat pulls the Kon-Tiki 90 kilometres out so that the journey begins beyond the ship’s routes. The men hoist the sail with the likeness of the sun god. They still know little of pre-Columbian sailing; no one has been able to teach them. They manoeuvre with a six-metre-long rudder, at the end of which a rudder blade dives into the sea. Soon the trade wind blows strongly and reliably billows the sail. Every two hours, the watch at the helm changes. To measure the speed, they throw a wooden chip into the sea at the bow and determine the time until it glides past the stern of the raft. From this they calculate the speed: frequently they manage more than 70 kilometres in a single day. They glide along like driftwood. Colourful tropical fish gather beneath them. In their sleep, the men feel as if they are on the back of a large, breathing animal, whose skeleton crunches and shrieks, cracks and screams on the waves, Heyerdahl notes.

Despite all the friction of the logs, the ropes do not chafe through: the sea has caused the outer layers of the balsa wood to swell, and so the ropes lie as if embedded in soft cork. The deck protrudes so little from the water that once a wave washes a strange fish into one of the sleeping bags: Gemphylus serpens, a snake mackerel never before observed alive by researchers. “Perhaps one must sail on a raft,” Heyerdahl notes, “to discover such strange fish.” 

Using fishing rods, they catch dolphinfish and yellowfin tuna, frying them on their stove next to the cabin. Researchers had previously assumed that marine animals were found primarily in offshore currents, and concluded that early seafarers would have starved to death on the open sea. But the adventurers find it easy to secure supplies. Sharks often circle around the raft. The crew collects rainwater in stretched canvas.

For weeks, the Kon-Tiki drifts westwards. Again and again, the men try to change the position of the sail to test the raft’s manoeuvrability. Only after six weeks do they finally discover the simple technique the pre-Columbian sailors must have used to navigate: by raising or lowering the centreboards. For the first time, Kon-Tiki´s crew gain control over their vessel and are able to determine the rough direction.

Heyerdahl collects plankton, keeps the logbook or films with his camera from the leashed dinghy. Then, on 21 July, the 85th day of their journey: the storm. The man overboard. The rescue at the last moment. The storm rages for five days, wind and waves tugging at the raft. The men survive only because they strictly adhered to the millennia-old construction plans when building the raft. Steel ropes would have sawn the raft in the storm—but the sisal ropes still lie securely in their notches. And if Heyerdahl’s team had used dried balsa wood in the construction, the logs would now be soaked with seawater and would sink. The sap, however, in the freshly cut trees apparently has an impregnating effect.

During the journey, the ocean supplies food. Sharks often circle around the raft. The men catch them with a hook and pull them on board.

Nine days later, on 30 July, seabirds circle the raft. A thin shadow looms on the horizon to the southeast. Puka Puka! An outpost of the Tuámotu archipelago in the outer east of Polynesia, the men conclude from their charts and measurements. But wind and ocean currents carry the Kon-Tiki past the island. A few days later, they see land for the second time: Fangatau, 6,853 kilometres from Peru. But Fangatau is enclosed by an impassable coral reef. 

On 7 August, they reach Raroia Atoll, part of the Tuámotu Archipelago. And this time they drift directly towards the island. Even from several hundred metres away, they can see powerful surf waves in the reef. Nevertheless, the cook calmly serves a meal. “The last one before the big joust,” as Heyerdahl quickly notes. Then he stows away his precious log book. 

At 9:50 a.m., one of the radio operators sends a message to a radio amateur on the island of Rarotonga further to the west, with whom he has been in contact since the previous day: If the crew does not respond within 36 hours, they should notify the Norwegian mission in Washington. Finally, he says, “OK, 45 metres to go. Here we go. Goodbye.”

As the raft approaches the reef, the men cling to the rigging. Waves push the craft up and crash over their heads. “Look at the raft, it’s holding! It’s holding!” one yells. But then an eight-metre-high wave rolls in and buries the Kon-Tiki underneath. The force snaps the mast and shatters the rudder. Crossbeams break. The deck rips open, the hut is compressed. The crew lies between ropes and the debris of the bamboo deck; only the nine thick balsa wood trunks have withstood the collision and are still moored.

A short time later, the wreck crashes against a step in the reef. Waves push it onto the stone roof of the coral garden. But even its sharp edges hardly damage the hull: although the corals have shaved six or seven centimetres off the mighty trunks in some places, they only cut four of the 300 ropes. All other sisal straps rest safely in their wooden notches. 

After about 7,000 kilometres, the Kon-Tiki has reached its destination. In the Rairoa Atoll, it strands on a coral reef.

From their wreck, the six men jump into the lagoon and wade to a small island on the atoll. After some 7,000 kilometres and 101 days at sea, they step ashore. No one is seriously injured. At most, they have suffered scratches and minor puncture wounds. The radio soon works again, too. The men send a message. And then plant a coconut from Peru. 

For six days they live on the uninhabited island. They salvage their boxes from the Kon-Tiki, feed on crabs, coconuts and fish. Then the white triangular sail of an outrigger canoe appears on the horizon. The adventurers wave a flag on the beach until two locals moor their canoe on the beach.

“Ja ora na!” shouts Heyerdahl to them in greeting, “Good day!”

“Ja ora na!” they reply.

A second canoe docks. One of the locals tells them they saw the glow of a fire nights ago. They invite the newcomers to their village across the lagoon. There the chief welcomes them. He, too, speaks French and calls the Kon-Tiki a pae-pae, the Polynesian word for raft. While the Polynesians admire the balsa wood logs, the chief tells them that his ancestors once sailed on pae-paes.

News of the landing has already spread around the world. A schooner is ordered to the island to take the crew and their raft to Tahiti. There the men are celebrated and baptised: with Tahitian chieftain names. Heyerdahl is invited all over the world; becomes an honorary member of dozens of geographical societies and one of the most famous natural scientists of the postwar period. Some 40 crews imitate his sailing on a primitive raft. Yet many experts remain sceptical. For them, Heyerdahl is just a “daring Viking”, his raft trip “a nice adventure”. 

On landing, the mast of the raft snaps. Its balsa trunks save the men from being injured by the sharp-edged corals. 

In the years following the voyage of the Kon-Tiki, circumstantial evidence contradicts Heyerdahl’s theories. Relics of the early Lapita culture are discovered on many Pacific islands. And the ancestors of this culture clearly came to the Pacific from the west. Language studies and genetic tests have also since shown that the roots of the fair-skinned, tall Polynesians lie less in the New World than in Asia.

Now however, more than 20 years after Heyerdahl’s death, studies seem to prove him partially right after all. In 2020, a team from Stanford University proved through genetic analyses of 807 people from Polynesia and South America that their ancestors must have been in contact early on—presumably around 800 years ago.

In the DNA of test subjects from the Marquesas, among other places, the researchers found genetic traces that must have come from ancestors of indigenous people from Colombia and southern Mexico. Another genetic study on the time frame of the settlement of the Eastern Pacific confirmed the results in September 2021.

Had pioneers from South America, as Heyerdahl suspected, already established themselves on some islands in the eastern Pacific when sailors from the western archipe-lagos first arrived there? Possible, and perhaps more likely, is the opposite scenario: daring explorers could have advanced from the Marquesas to South America and then returned accompanied by indigenous people from the mainland. 

One thing is certain: long before the arrival of the Europeans, America and the South Seas were engaged in a nautical exchange—just as Heyerdahl’s raft voyage was to prove. Genetic analyses suggest that the first contact probably took place on Fatu Hiva—where the Kon-Tiki adventure also began. 

FROM GEO (February 2022); © Dirk Liesemer, Lars Abromeit/Geo/DDP