| 100% | POTOMAC | 7 | River that flows between Maryland and Washington, DC |
| 51% | POTOMAC | 7 | River that Alexandria, VA and Washington, DC lie on |
| 48% | DOURO | 5 | River that forms part of the border between Spain and Portugal before flowing west to the Atlantic |
| 45% | WYE | 3 | Maryland river that lent its name to the memorandum negotiated between Israel and the Palestinian Authority in 1998 |
| 45% | CAM | 3 | River that flows through and is hidden in "Cambridge" |
| 45% | AIRE | 4 | River that flows through Leeds and Skipton |
| 45% | DANUBE | 6 | River that flows through Budapest and Belgrade |
| 45% | DNIEPER | 7 | River that flows through Russia and Ukraine |
| 45% | POTOMAC | 7 | River that borders Washington, DC |
| 44% | POTOMAC | 7 | River that Washington DC stands on |
| 44% | POTOMAC | 7 | River that runs through Washington DC |
| 43% | RHINE | 5 | River that flows through Germany and the Swiss Alps |
| 43% | INDUS | 5 | Major river that flows through China, India and Pakistan |
| 43% | RANCE | 5 | River in NW France that flows into the English Channel between Dinard and Saint-Malo |
| 42% | MORAVA | 6 | River that forms the border between Slovakia and Austria |
| 42% | AMUR | 4 | River that forms the boundary between Manchuria and Russia |
| 42% | MEKONG | 6 | River that forms the border between Laos and Myanmar |
| 42% | IDAHO | 5 | State that's between Montana and Washington |
| 42% | TWRCH | 5 | River that formed the ancient boundary between Brecknockshire and Carmarthenshire |
| 41% | EUPHRATES | 9 | Major river that flows through Iraq and Syria |
| 41% | DRINA | 5 | River that forms the boundary between Bosnia and Herzegovina and Montenegro |
| 41% | ODER | 4 | River that forms part of the border between Germany and Poland |
| 41% | TAMAR | 5 | River that forms most of the border between Cornwall and Devon |
| 41% | EBRO | 4 | River that was the ancient dividing line between Rome and Carthage |
| 41% | ORINOCO | 7 | River that forms part of the border between Colombia and Venezuela |
| 41% | MOSELLE | 7 | River that forms part of the border between Germany and Luxembourg |
| 41% | DOURO | 5 | River that forms part of the border between Spain and Portugal |
| 41% | LIMPOPO | 7 | River that serves as the border between Zimbabwe and South Africa |
| 41% | RIONEGRO | 8 | River that forms part of the border between Colombia and Venezuela |
| 40% | ELBE | 4 | River that formed part of the border between East and West Germany |