WASHINGTON (Reuters) -- A five-nation expedition has determined the precise
                  source of the Amazon River in southern Peru through the use of advanced
                  satellite navigation technology, the National Geographic Society said Thursday.

                  The team used Global Positioning System equipment to take measurements that
                  precisely confirm the ultimate source of the river as a stream beginning on
                  Nevado Mismi, a mountain in southern Peru, NGS said in a statement.

                  In recent years, at least one other stream flowing from a separate peak had been
                  identified as the source of the mighty Amazon, one of the world's longest rivers.

                  The Amazon springs from the Andes' high glacial regions and the riddle about its
                  source has inspired speculation for centuries.

                  National Geographic said the GPS equipment used by the expedition was
                  considered accurate to within 1 to 5 meters. GPS receivers use orbiting satellites
                  as reference points to pin point locations on the Earth's surface.

                  "The trip's result is a highly reliable map of the Amazon's headwaters and an
                  accurate determination of the river's source," said Andrew Pietowski, a
                  mathematics teacher from Carmel, New York, who led the expedition.

                  "I was delighted to lead the team of explorers and scientists, despite what we had
                  to overcome -- cold, vicious winds and temperatures well below zero Fahrenheit,
                  high altitude and very rough terrain," he added.

                  Pietowski's team members -- representing the United States, Poland, Peru,
                  Canada and Spain -- traveled by foot, jeep, bicycle and horseback to explore the
                  five remote Andean rivers that combine to form the Amazon.

                  Smithsonian Institution geographer Andrew Johnson said the source of the
                  Amazon could be defined as the most distant point in the drainage basin from
                  which surface water ran year round, or the furthest point from which water
                  could possible flow to the Atlantic.

                  "The Nevado Mismi fits both of these definitions," said Johnson, who directed
                  the GPS work.

                  National Geographic said the July 2000 expedition was the culmination of four
                  reconnaissance trips in 1998 and 1999.

                      Copyright 2000 Reuters.