| Estimated Length | Country/Countries It Flows Through | River | % Correct |
|---|---|---|---|
| 3,970 miles | Brazil, Peru, Bolivia, Colombia . . . | Amazon River | 100%
|
| 4,160 miles | Egypt, Sudan, Kenya, Tanzania . . . | Nile River | 100%
|
| 3,710 miles | United States, Canada | Mississippi River | 95%
|
| 3,915 miles | China | Yangtze River | 93%
|
| 3,395 miles | China | Huang He River | 88%
|
| 2,920 miles | Rwanda, Zambia, Cameroon, DRC . . . | Congo River | 83%
|
| 2,700 miles | China, Vietnam, Thailand, Laos . . . | Mekong River | 76%
|
| 2,610 miles | Nigeria, Mali, Niger, Guinea . . . | Niger River | 72%
|
| 2,270 miles | Russia | Volga River | 71%
|
| 3,360 miles | Russia, Kazakhstan, China, Mongolia | Ob River | 61%
|
| 2,761 miles | Russia, China, Mongolia | Amur River | 56%
|
| 2,730 miles | Russia | Lena River | 56%
|
| 2,280 miles | Australia | Murray River | 53%
|
| 2,630 miles | Canada | Mackenzie River | 41%
|
| 2,470 miles | India, Nepal, Bangladesh, Bhutan . . . | Brahmaputra River | 39%
|
| 3,030 miles | Brazil, Argentina, Paraguay, Bolivia . . . | Rio de la Plata River | 32%
|
| 2,270 miles | Brazil | Tocantins River | 23%
|
| 3,440 miles | Russia, Mongolia | Yenisey River | 23%
|
| 2,100 miles | Brazil, Bolivia, Peru | Madeira River | 16%
|
| 2,230 miles | Iraq, Turkey, Syria, Iran | Shatt al-Arab River | 15%
|