and the river itself is the main highway for those traveling through the region. Macapá, on the north shore of the Amazon delta, is a city of half a million people, but there's not a single road ...

Researchers on an expedition in the Amazon River Delta have found mangroves growing in freshwater — a phenomenon never before documented in deltas or coastal mangroves anywhere else in the world.

Then, in 1971, a National Geographic expedition led by Loren McIntyre identified the snow-capped peak of Mismi (map) as the headwaters of the Apurímac River and the ultimate source of the Amazon.

The expedition has already secured some prestigious partnerships: support from the Explorers Club, an IMAX deal for a related film production and an assignment to produce a new Amazon river map ...