1. Nile River – 6,693 km 

Although most of us recognize the Nile as the lifeline of Egypt, the Nile is, in fact, an international river shared by 11 countries in Africa. However, it is the main source of water in two countries: Egypt and Sudan. The Blue and the White Nile are the two tributaries of the river with the latter having a greater length than the former. The source of the White Nile is not yet fully determined but is believed to be somewhere in Burundi or Rwanda. According to some reports, Lake Victoria is considered to be the source of the White Nile which is, in turn, fed by the Kagera River whose two major tributaries are the Ruvyironza and the Nyabarongo rivers of Burundi and Rwanda, respectively. The Kagera is formed at the confluence of these two rivers near the Tanzania-Rwanda border. The Blue Nile has a more defined origin in Lake Tana in Ethiopia. The two tributaries meet near the Sudanese capital of Khartoum. The Nile River’s final course is through Egypt before it forms a delta and drains into the Mediterranean Sea. According to the USGS, the length of the Nile River is 4,258 miles. It is the longest river in the world as well as the longest river in Africa. 

2. Amazon River – 6,436 km 

The Amazon River is undoubtedly the largest river in the world by discharge volume of water. However, its position as the second-longest river in the world is highly disputed as the title has for long been granted to the Nile River in Egypt. The dispute arises from the determination of the origin of the Amazon. Until now, the headwaters of the Apurímac River were considered to be the origin of the Amazon River. However, a recent 2014 study claims that the origin of the Amazon can be traced to the Cordillera Rumi Cruz from where Peru’s Mantaro River originates. This river then confluences with the Apurímac River (whose headwaters were earlier regarded as the source of the Amazon) and then other tributaries join the river downstream to form the Ucayali River which finally confluences with the Marañón River to form the main stem of the Amazon River. However, critics of this measurement point out that the study has not been published. 

3. Yangtze River – 6,378 km 

The Yangtze River is the world’s third longest river and the longest to flow entirely within one country. It is also Asia’s longest river. The river basin of the Yangtze houses one-third of the population of China, the most populated country in the world. Two origins of the Yangtze River has been suggested. Traditionally, the government of China recognizes the Tuotuo tributary located in the Tanggula Mountains as the source of the river. At 17,526 ft above sea-level, it is definitely the highest source of the Yangtze. According to new data, however, the source of the Yangtze River is located in the Jari Hill from where the headwaters of the Dam Qu tributary originate. These tributaries, and more join to form the mighty Yangtze River which finally drains into the East China Sea at Shanghai.

4. Mississippi/Missouri – 5,970 km 

The river system comprising of the Mississippi, Missouri, and Jefferson rivers, is regarded as the world’s fourth longest river system. The river system drains 31 US states and 2 Canadian provinces. The Mississippi River begins in northern Minnesota where Lake Itasca is believed to be the origin of the river and drains into the Gulf of Mexico. However, when we regarded the Jefferson River as the furthest source of the Mississippi River, then we get the Mississippi–Missouri–Jefferson river system. 

5. Yenisei/Angara – 5,539 km 

This is the world’s fifth-longest river system and the largest draining into the Arctic Ocean. The Selenge River is regarded as the headwaters of this river system. The Selenge River is 992 km long and drains into Lake Baikal. The Angara river rises from Lake Baikal near Listvyanka and flows through the Irkutsk Oblast of Russiaand finally joins the Yenisei River near Strelka. The Yenisei finally drains into the Arctic Ocean. The total length covered is 5,539 miles.