The 10 Longest Rivers in South America

Amazon River with Capybaras

Written by Kyle Glatz

Updated: June 28, 2023

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South America is rife with unique animals and many bodies of water. Of course, the most famous body of water in South America is the Amazon River. However, it’s not the only river worth talking about in this part of the world, and it’s not even the only one over 3,000 miles long! Today, we’re going to take a look at the 10 longest rivers in South America and show you all the other very long rivers that get overlooked!

Discover the 10 Longest Rivers in South America

South America is home to many bodies of water across various climates.

South America has many large bodies of water located in and around the Amazon Rainforest along with the east coast of the continent. These rivers range in length and some of them are tributaries for some and affluents of others.

Some of the river measures in South America are contested. The placement of these rivers on the list may change with time. As new techniques for finding the headwaters of a river become available, the true lengths (and thus the rankings) will become less fluid.  

Infographic of 10 Longest Rivers in South America
The lengths of several rivers in South America are contested so these rankings may change in future.

10. Orinoco River: 1,400 Miles

Orinoco River

The Orinoco River is known as the home of the pink Amazon River dolphin and the Orinoco



The Orinoco River measures about 1,400 miles, starting in Venezuela and flowing to its mouth at the Gulf of Paria. The river is famous for being home to the pink Amazon River dolphin as well as the Orinoco crocodile, a scarcely seen reptile. Aside from wildlife, the river is an important economic artery for transporting goods, and it is also home to several courses of rapids, so it is a popular area for watersports.

9. Paraguay River: 1,584 Miles

Paraguay River

The Paraguay River measures 1,584 miles long and reaches its mouth at the Paraná River.

The Paraguay River begins in the Parecis plateau in Brazil and flows southwest throughout its run. The river measures 1,584 miles long, and it eventually reaches its mouth at the Paraná River, a location that runs between Paraguay and Argentina.

8. Japurá River: 1,750 Miles

Japurá river

The Jupura River is home to animals including piranhas, caimans, and electric eels

The Japurá River is also known as the Caquetá River, and it flows from the western portion of Colombia into Brazil. The total length of the river’s run is 1,750 miles. Throughout this run, the river helps provide water for agriculture in areas that have been recently cleared for farmland.

The river is known for being somewhat hard to navigate while also being filled with many sorts of large fish. Some of the common inhabitants of the river are piranhas, caimans, and the interesting electric eel! The Japura River’s mouth is the Amazon River.

7. São Francisco River: 1,976 Miles

Sao Francisco River

The São Francisco River flows through diverse climates like arid areas.

The São Francisco River flows solely in Brazil despite being one of the largest rivers on the continent. The waters rise in Canastra Mountains and flow until the river hits the Atlantic Ocean.

This river is known for flowing through diverse climates in the country as well as being home to hydroelectric projects that generate power. Like some other rivers on this list, the São Francisco River’s true length is up for debate. Some sources list 1,976 miles and others stick to 1,802 miles; we’ve chosen the latter.

6. Juruá River: 2,040 Miles

Juruá River

Reaching the Amazon River after a 2,040-mile journey, the Juruá River is one of the longest in South America.

The Juruá River is a tributary of the Amazon River. It has a source in Peru and flows 2,040 miles to reach the confluence with the Amazon River. The river is known for its meandering flow and the fact that over half of the river is completely unobstructed, allowing for economic development to take place along its banks.

The length of this river is up for debate. Some sources list it as being as short as 1,500 miles or 1,926 miles, but others grant it the length of 2,040 miles, the measure used for this list.  

5. Madeira-Mamoré River: 2,100 Miles

Madeira-Mamore River

The Madeira-Mamoré River is mostly navigable, especially during the rainy season.

The Madeira-Mamoré River is a major river that forms from its confluence with the Mamoré River, a river that begins at the Sierra de Cochabamba. The combined lengths of these two rivers, which form a long, connected body of water, measure 2,020 miles or 2,100 miles.

Like many other important rivers in South America, this river’s mouth is the Amazon River. Although the rivers are mostly navigable, especially during the rainy season, two dams are being built to provide the area with hydroelectric power.

4. Purús River: 2,101 Miles

Purus River

Meandering for more than 2,100 miles, the Purús River is the fourth-largest in South America.

The Purús River measures slightly more than the Madeira-Mamoré River. There may be as little as a mile separating the two rivers in terms of length. The river forms at a confluence with the Cujar and Curiuja Rivers, and then it flows for 2,101 miles. At the end of the flow, it meets the Amazon River.

The river flows through areas of South America with high levels of biodiversity for mammals and fish alike.

3. Tocantins-Araguaia River: 2,270 Miles

Javaés River

The Tocantins-Araguiaia River has massive hydroelectric dams.

The combined length of the Tocantins-Araguaia River system is 2,270 miles. The Tocantins portion is a clearwater river that begins in the state of Goias, Brazil. The river is known for the massive hydroelectric dam on its borders. Both rivers are known for being high in biodiversity.

This river basin for this river is home to hundreds of species of birds and fish, including some of the largest and rarest animals in Brazil.

2. Rio de la Plata-Paraná River: 3,030 Miles

Rio de la Plata runs through Argentina and Uruguay.

The Rio de la Plata-Parana River system measures over 3,000 miles long. The Parana River makes up the bulk of the river. The Parana River begins at the Paranaiba River and flows almost to the end of its run before it reaches its mouth in the Rio de la Plata.

However, the Rio de la Plata is interesting in its own right for being such a wide river. In fact, the Rio de la Plata is the widest river in existence if it’s not considered an estuary, gulf, or other body of water instead.

The river is famous for being the site of the Battle of the River Plate in World War II. Buenos Aires is situated on the southern coast of the river. The Rio de la Plata runs into the Atlantic Ocean at its end.

1. Amazon River: 3,976 Miles

The Amazon River’s length is a point of contention among scientists.

The Amazon River is the longest river in South America. That fact doesn’t come as a surprise to most people. However, the length of the river is both incredibly long and controversial.

Scientists have agonized over finding the true length of this immense river that supports human and animal life alike. One study suggests that the Amazon River is truly 4,344 miles long, but another study claims it’s 4,345 miles long.

Depending on the measurement, the Amazon River could be a contender for the largest river in the world. For now, though, most accept that the Nile River is longer.  

South America’s rivers are not often recognized for their length, aside from the Amazon River. Still, the longest rivers in South America often measure over 2,000 miles and can even hit 4,000 miles if the latest studies are true.

Summary of the 10 Longest Rivers in South America

Here’s a recap of the rivers located in South America that flow for the longest distances.

1Amazon RiverPeru, Ecuador, Colombia, Venezuela, Bolivia, and Brazil3,976 miles
2Rio de la Plata-Paraná RiverBrazil, Paraguay, Uruguay, and Argentina3,030 miles
3Tocantins-Araguaia RiverBrazil2,270 miles
4Purús RiverPeru and Brazil2,101 miles
5Madeira-Mamoré RiverBolivia and Brazil2,100 miles
6Juruá RiverPeru and Brazil2,040 miles
7São Francisco RiverBrazil1,976 miles
8Japurá RiverColumbia to Brazil1,750 miles
9Paraguay RiverBrazil, Bolivia, Paraguay, and Argentina1,584 miles
10Orinoco RiverVenezuela and Columbia1,400 miles

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About the Author

Kyle Glatz is a writer at A-Z-Animals where his primary focus is on geography and mammals. Kyle has been writing for researching and writing about animals and numerous other topics for 10 years, and he holds a Bachelor's Degree in English and Education from Rowan University. A resident of New Jersey, Kyle enjoys reading, writing, and playing video games.

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