The Napo River (Spanish: Río Napo) is a tributary to the Amazon River that rises in Ecuador on the flanks of the east Andean volcanoes of Antisana, Sincholagua and Cotopaxi. The total length is 1,075 km (668 mi). The river drains an area of ca 103,000 km2. The mean annual discharge at Mazán 6,800 m3/s (240,000 cu ft/s).
