Humans have long depended on rivers. From the earliest bits of recorded history, access to reliable sources of freshwater proved instrumental in allowing societies to flourish. Rivers help irrigate crops and support major cities. Rivers nourish wildlife in diverse landscapes and provide recreational opportunities. It’s no exaggeration to say human civilization is inexorably bound to major rivers. In selecting our picks for the world’s most beautiful and important rivers, we considered a number of factors beyond simply length and historical significance.

1. Nile River

  • Length: 6,650 km
  • Mouth: Mediterranean Sea
  • Countries: Egypt, Sudan

The Nile is a major north-flowing river in northeastern Africa. It flows into the Mediterranean Sea. The Nile is one of the world’s great waterways, at 4,180 miles (6,695 kilometers) generally regarded as the longest river in the world and among the most culturally significant natural formations in human history. Flowing northward from remote sources in the mountains of Ethiopia and central Africa and draining into the Mediterranean Sea, the Nile has flooded seasonally over millennia to provide life-giving fertile soils and irrigation for Egypt’s people. The drainage basin of the Nile encompasses about 10 percent of the area of Africa. The soil of the Nile River delta between El Qâhira (Cairo) and the Mediterranean Sea is rich in nutrients, due to the large silt deposits the Nile leaves behind as it flows into the sea. The banks of the Nile all along its vast length contain rich soil as well, thanks to annual flooding that deposits silt. From space, the contrast between the Nile’s lush green river banks and the barren desert through which it flows is obvious.

2. Amazon River

  • Length: 6,400 km
  • Mouth: Atlantic Ocean
  • Countries: Brazil, Peru, colombia

The Amazon River in South America is the largest river by discharge volume of water in the world, and the disputed longest river in the world in comparison to the Nile. The Amazon River sets the record in terms of the sheer volume of water that it carries – a mind-boggling average discharge of 219,000 m3/sec of water. It is estimated that approximately one-sixth of all fresh water that drains into the world’s oceans goes through the 320-km-wide delt  of the Amazon, where it meets the Atlantic Ocean. During the dry season, the width of the Amazon River can be 4 km to 5 km in places – and in the wet season, this can increase to 50 km! At the height of the wet season, the current can reach a speed of 7 km/hr. As the drainage system of the Amazon Basin, the Amazon River and its approximately 1,100 tributaries play major roles in the ecology of the basin. Before roads and airstrips started appearing in the basin, these waterways were the major access routes to the interior areas of Brazil and the northern half of South America. The brown waters of the Amazon River can be seen as far as 100 km out to sea from the mainland, well before the continent is in sight.

3. Yangtze River

  • Length: 6,300 km
  • Mouth: East China Sea
  • Countries: China

The Yangtze, Yangzi, or officially Chang Jiang is the longest river in Asia, the third-longest in the world and the longest in the world to flow entirely within one country. It rises at Jari Hill in the Tanggula Mountains and flows 6,300 km in a generally easterly direction to the East China Sea. The Yangtze’s rich and complex terrains and climate have created a wide range of natural ecosystems that provide vital habitats for such charismatic species as the 4snow leopard, giant panda, and Yangtze finless porpoise. Historically, it has also sustained numerous local communities that rely on the river for drinking water, farming, fishery, and transportation. But unprecedented economic growth, combined with expansion of industries and rapid urbanization, in the basin is putting a severe strain on the river. The river originates in a glacier in the Dangla mountains on the eastern part of the Tibetan plateau. It then runs through the eastern part of Qinghai, turning southward down a deep valley at the border of Sichuan and Tibet to reach Yunnan. In the course of this valley, the river’s elevation drops from above 5000 m to less than 1000 m. It enters the basin of Sichuan at Yibin. While in the Sichuan basin it receives several mighty tributaries, increasing its water volume significantly.

4. Danube River

  • Length: 2,850 km
  • Mouth: Denube Delta
  • Countries: Germany, Romania, Ukraine, hungary

The Danube is the second-longest river in Europe, after the Volga in Russia. It flows through much of Central and Southeastern Europe, from the Black Forest into the Black Sea. It begins in the Black Forest region of Germany and runs through 10 countries (Germany, Austria, Slovakia, Hungary, Croatia, Serbia, Romania, Bulgaria, Moldova and Ukraine) on its way to the Black Sea. Much older than the Rhine, its basin is thought to have been the site of some of the earliest human cultures, and it remains one of Europe’s most important and historic waterways and a popular river cruise destination. Find itineraries for Danube river cruises from Viking River Cruises. Oddly enough, the waterway is not called “Danube” in any of the countries through which it runs. In German, it is the Donau; in Czech, the Dunaj; in Hungarian, the Duna and so forth. Worshipping a god of the same name, the ancient Romans called the waterway Danubius. All these names derive from the Celtic word danu, which means “to flow” or “to run.”