The Rio Negro flows through the eastern edge of Brazil’s Jau National Park. The river is the big strip of blue running from left to right across the image, and the other blue ribbons are tributaries. It starts at the border of Venezuela and Brazil, and meets up with the Amazon in central Brazil. Half-submerged islands can be seen in the center of the river. Between November and April when the river is at its peak, many of these islands disappear.