A river flows from its source to its mouth, as you learned in A River's Journey. The world's great rivers have carried people and goods for thousands of years, and many of the oldest cities grew up along them.
Key idea
The great rivers to know: the Nile and Congo (Africa), the Amazon (South America), the Mississippi (North America), the Yangtze, Ganges and Mekong (Asia), and the Danube and Volga (Europe).
| River | Continent | Flows into |
|---|---|---|
| Nile | Africa | Mediterranean Sea (flowing north) |
| Amazon | South America | Atlantic Ocean |
| Yangtze (Chang Jiang) | Asia (China) | East China Sea, Pacific |
| Mississippi | North America | the Gulf of Mexico (since 2025 the U.S. federal government calls it the Gulf of America) |
| Congo | Africa | Atlantic Ocean |
| Ganges | Asia (India, Bangladesh) | Bay of Bengal |
| Mekong | Asia (Southeast) | South China Sea |
| Danube | Europe | Black Sea |
| Volga | Europe (Russia) | Caspian Sea |
Why it works
Rivers flow downhill, so the direction depends on where the high ground is, not on north and south. The Nile starts in the highlands of East Africa and flows north to the Mediterranean. Some record holders: the Amazon carries the most water, about a fifth of all the river water that reaches the oceans; the Yangtze is the longest river in Asia; the Volga is the longest in Europe; the Danube flows through or along ten countries.
Worked example: Which way?
Cairo is near the Nile's mouth. Is Cairo upstream or downstream from Khartoum, Sudan, which is south of it?
- The Nile flows north, into the Mediterranean.
- Water at Khartoum flows on north toward Cairo.
- So Cairo is downstream.
Answer: Downstream.
Common mistake
Thinking the Nile flows south because Egypt is at the "top" of Africa and things fall "down" on a map. North is not downhill. And which river is longest? Most lists put the Nile first (about 6,650 km) with the Amazon close behind, but some studies that trace the Amazon from a farther source find it longer. The answer depends on where you say a river begins.