What is the longest river in the Patagonia (southern Argentina)?

Question

What is the longest river in the Patagonia (southern Argentina)?

Answer 1

The Colorado River

"The river flows generally east-southeastward across the arid terrain of northern Patagonia and the southern Pampas and is a border for four provinces. Its lower course splits into two arms, which flow into the Atlantic Ocean south of Bahía Blanca. The total length of the Colorado is about 530 miles (850 km)."

"Argentina’s varied geography can be grouped into four major regions: the Andes, the North, the Pampas, and Patagonia. The Andean region extends some 2,300 miles (3,700 km) along the western edge of the country from Bolivia to southern Patagonia, forming most of the natural boundary with Chile. It is commonly subdivided into two parts: the Northwest and the Patagonian Andes, the latter of which is discussed below under Patagonia. The North is commonly described in terms of its two main divisions: the Gran Chaco, or Chaco, comprising the dry lowlands between the Andes and the Paraná River; and Mesopotamia, an area between the Paraná and Uruguay rivers. The centrally located plains, or Pampas, are grasslands subdivided into arid western and more humid eastern parts called, respectively, the Dry Pampa and the Humid Pampa. Patagonia is the cold, parched, windy region that extends some 1,200 miles (1,900 km) south of the Pampas, from the Colorado River to Tierra del Fuego."

I hope this helps you.  Good luck.

Answer 2

i think it might be the Futaleufu River -

The Futaleufu River is a river fed by the lakes in the Los Alerces National Park in Chubut Province, Argentina, crossing the Andes Mountains into Chile and opening into the Yelcho Lake.