Negro
Top 3 in Top 8 Longest Rivers in Colombia
The Negro river, or Guaina in its upper reaches, is the Amazon River's greatest left tributary (accounting for roughly 14% of the water in the Amazon basin), the world's largest blackwater river, and one of the top 10 rivers by average discharge.
The river was named after Francisco de Orellana, a Spanish explorer who first discovered it in 1541. By the mid-seventeenth century, Jesuits had established themselves along the river's banks, amidst a diverse tribe of Manau, Aruák, and Trumá Indians. Slavery along the river became popular after 1700, and Native American populations suffered tremendously as a result of Eurasian diseases. This area was also where filming for Survivor:The Amazon in 2003.
While the name Rio Negro refers to "Black River," the Rio Negro's waters have the color of strong tea, as is common of blackwater rivers. The black hue derives from humic acid, which is formed when phenol-containing plants from sandy clearings is not completely broken down. The river was given its name because it seems black from a distance.
Length: 1,386 miles (shared with Brazil and Venezuela)
