Book: Kon-Tiki

Overview
Thor Heyerdahl’s Kon-Tiki recounts a daring 1947 expedition designed to test an unconventional idea about the peopling of Polynesia. Convinced that ancient South Americans could have reached the Pacific islands on simple balsa rafts, Heyerdahl built such a craft using pre-Columbian methods and, with five companions, sailed it from Peru into the open ocean. The book blends scientific provocation with an adventure narrative, following the crew for 101 days and more than 4,300 miles until their landfall on a remote atoll in the Tuamotus.

Hypothesis and Motivation
Heyerdahl’s theory grew from years spent in Polynesia, where he noticed cultural echoes and biological clues, especially the presence of the sweet potato, a South American crop, alongside Polynesian legends of a bearded culture hero named Tiki. He argued that winds, currents, and available materials could have made a westward drift voyage feasible. Dismissed by academic authorities, he resolved to test the possibility at full scale, emphasizing that success would show only that such a journey was possible, not that it actually occurred.

Building the Raft and Assembling the Crew
In Callao, Peru, the team lashed nine massive balsa logs into a buoyant, flexible platform, pinned and roped without nails in the manner Heyerdahl believed pre-Columbian mariners used. A small thatched cabin and a single mast with a square sail, painted by navigator Erik Hesselberg with a stylized face of the god Kon-Tiki, completed the craft. Steering relied on a giant stern sweep and a set of movable wooden centerboards, or guaras, that altered the raft’s underwater profile. While the build honored ancient techniques, the crew prudently carried a sextant, provisions, and radio sets. The team was a mix of specialists and wartime veterans: Heyerdahl; Hesselberg; Swedish ethnographer Bengt Danielsson; radio operators Knut Haugland and Torstein Raaby; and engineer Herman Watzinger. They also adopted a green parrot, Lorita.

The Pacific Crossing
Pushed by the Humboldt Current and steadied by the southeast trades after launching on April 28, 1947, the Kon-Tiki found her rhythm as a slow, stubbornly seaworthy craft. Daily life became a pattern of keeping watch, tending gear, navigating by sun and stars, and fishing the living sea that surrounded them. Flying fish flopped aboard at night; dorado and sharks struck their lines; the raft’s underside sprouted barnacles and became an ecosystem that drew larger predators. Through Hesselberg’s observations and the guaras, the crew learned to “trim” the raft to wind and wave rather than force a course like a keelboat.

Hazards, Wonders, and Proof of Seaworthiness
Storms, squalls, and long swells tested the lashings and the men. A whale shark loomed beneath the logs, and surfacing whales rolled past, indifferent. A breaking sea snapped the steering oar, demanding improvised repairs. The radio, tended by Haugland and Raaby, linked the raft to distant operators, a comfort and a safety net when the sky closed in. The raft’s flexibility, so counterintuitive to modern seamen, proved its genius: instead of fighting waves, Kon-Tiki yielded and survived. The men ate well on fish and coconuts and kept spirits with stories and sketches; only Lorita was lost, swept away by a sudden squall.

Landfall and Aftermath
Near the Tuamotus, the crew sighted birds and driftwood, then the thin green lines of low coral islands. With no pass in sight and heavy surf running, the current drove the raft onto the reef of Raroia on August 7. The logs wedged fast; the men swam to a nearby motu and later salvaged gear. Islanders soon appeared by canoe, welcoming the strangers who had arrived as the old stories said, out of the east on a raft. The expedition had shown that a balsa craft, built with ancient means, could cross the Pacific on currents and trades. Heyerdahl closes by reflecting on open-sea possibility and the value of testing ideas against wind and water.