The Kon-Tiki adventure

In 1947, Thor Heyerdahl sailed his balsa wood raft, the Kon-Tiki, across the Pacific Ocean to add weight to his belief that ancient peoples were capable of long sea journeys.

He also wanted to prove that it was possible that Polynesia was first colonised by natives of South America.

(Image: The Kon-Tiki raft. Credit: Getty Images)