Into the unknown: how great explorers found their way by land, sea, and air

Fourteen amazing journeys: 340 BC Pytheas the Greek sails to the Arctic Circle

AD 1003 Leif Eriksson reaches the coast of America

1271-1274 Marco Polo rides the Silk Road to China

1405-1407 Admiral Zheng He crosses the Indian Ocean

1492 Christopher Columbus sails to the Caribbean

1519-1522 Ferdinand Magellan's fleet circumnavigates the world

1768-1771 Captain Cook maps the Pacific Ocean

1858-1864 David Livingstone explores the Zambezi River

1895 Mary Kingsley travels alone in West Africa

1928 Umberto Nobile flies over the North Pole

1932 Auguste Piccard ascends into the stratosphere

1960 Jacques Piccard dives to the Challenger Deep

1953 Edmund Hillary & Tenzing Norgay climb Everest

1969 Neil Armstrong & Buzz Aldrin land on the moon.