I happened to borrow this movie from a friend knowing nothing about it, and it turned out to be an outstanding documentary about a journey on an ancient vessel across vast expanses of the ocean. Thor Heyerdahl had developed a theory that the ancient Incas in Peru managed to travel thousands of miles across the ocean to Polynesia, based on certain relics that are found in both places, certain types of ancient sea-going vessels that we know they had available, analysis of ocean and wind currents, and the knowledge that the Incas did, in fact, travel in some undetermined amount at sea.
In order to test his hypothesis, Heyerdahl and his crew construct a vessel as closely as possible to what the ancient Incas had available, using only balsa wood and other materials available at the time, and set out from Lima, Peru's capital, to try to reach the islands of Polynesia, some 5,000 miles away.
His theory, like so much about ancient history, is impossible to prove with 100% certainty, but the coverage of their journey provides for strong support that he is right. The film is really little more than narration of footage taken during the 100+ day expedition, but it is a very detailed description of what it was like and the trials and tribulations that they faced. I often wish that Academy Award winning documentaries were easier to find, and this one from more than 50 years ago is still as interesting and informative as I am sure it was when it was first released.
