| km² | River Basin | % Correct |
|---|---|---|
| 185 k | Rhine | 99%
|
| 802 k | Danube | 98%
|
| 1433 k | Volga | 94%
|
| 75.4 k | Seine | 91%
|
| 73.7 k | Po | 88%
|
| 510 k | Dnieper | 87%
|
| 98.1 k | Rhone | 87%
|
| 148 k | Elbe | 81%
|
| 117 k | Loire | 80%
|
| 437 k | Don | 78%
|
| 193 k | Vistula | 74%
|
| 119 k | Oder | 66%
|
| 73.2 k | Dniester | 65%
|
| 84.8 k | Ebro | 63%
|
| 70.8 k | Tagus | 62%
|
| 211 k | Ural | 58%
|
| 97.3 k | Douro | 48%
|
| 55.8 k | Garonne | 44%
|
| 85.6 k | Daugava | 41%
|
| 46.3 k | Weser | 39%
|
| 281 k | Neva | 38%
|
| 57.1 k | Guadalquivir | 29%
|
| 92.5 k | Neman | 27%
|
| 357 k | Northern Dvina | 27%
|
| 322 k | Pechora | 21%
|
| 67.0 k | Guadiana | 16%
|
| 52.4 k | Kuban | 16%
|
| 56.2 k | Narva | 15%
|
| 63.6 k | Southern Bug | 15%
|
| 56.9 k | Onega | 12%
|
| 53.5 k | Maritsa | 11%
|
| 78.0 k | Mezen | 11%
|
| 51.1 k | Kemijoki | 9%
|
| 50.2 k | Göta älv | 8%
|