Which river and its tributaries are the northermost South American river system?

The Orinoco and its tributaries constitute the northernmost of South America’s four major river systems. It is a major river of South America that flows in a giant arc for some 1,700 miles (2,740 km) from its source in the Guiana Highlands to its mouth on the Atlantic Ocean. Throughout most of its course it flows through Venezuela, except for a section that forms part of the frontier between Venezuela and Colombia. The name Orinoco is derived from Warao (Guarauno) words meaning “a place to paddle”

The climate of the Orinoco basin is tropical, with the seasons marked by differences in rainfall rather than in temperature. The year is divided into two seasons—rainy and dry (locally known as winter and summer)

More than 1,000 species of birds frequent the Orinoco region; among the more spectacular are the scarlet ibis, the bellbird, the umbrella bird, and numerous parrots.

Except for the Guajiros of Lake Maracaibo, most of the Venezuelan aboriginal population lives within the Orinoco River basin. These peoples live in intimate relationship with the rivers of the basin, using them as a source of food as well as for purposes of communication.