| Rio Negro Bridge, Amazon Theatre - Manaus, Praia da Ponta Negra, Amazônia Arena, Palácio Rio Negro|Meeting of Waters Wikipedia
The Meeting of Waters (Portuguese: Encontro das Águas) is the confluence between the dark (blackwater) Rio Negro and the pale sandy-colored (whitewater) Amazon River or Rio Solimões, as the upper section of the Amazon is known in Brazil upriver of this confluence. For 6 km (3.7 mi) the two rivers' waters run side by side without mixing. It is one of the main tourist attractions of Manaus, Brazil. The same also happens near Santarém, Pará with the Amazon and Tapajós rivers. This phenomenon occurs in other regions of the world with differing characters of rivers.
This phenomenon is due to the differences in temperature, speed and water density of the two rivers. The Rio Negro flows at near 2 km/h (1.2 mph) at a temperature of 28 °C (82 °F), while the Rio Solimões flows between 4 and 6 km/h (2.5–3.7 mph) at a temperature of 22 °C (72 °F).