| Length (km) | Answer | % Correct |
|---|---|---|
| 346 | River Thames | 99%
|
| 354 | River Severn | 89%
|
| 118 | River Tyne | 78%
|
| 297 | River Trent | 67%
|
| 120 | River Avon (Bristol) | 65%
|
| 154 | River Avon (Warwickshire) | 65%
|
| 113 | River Mersey | 62%
|
| 208 | River Ure / Ouse (Yorkshire) | 55%
|
| 113 | River Tees | 44%
|
| 215 | River Wye | 41%
|
| 112 | River Don (South Yorkshire) | 27%
|
| 120 | River Ribble | 26%
|
| 155 | River Tweed | 26%
|
| 115 | River Derwent (Yorkshire) | 24%
|
| 113 | River Medway | 22%
|
| 114 | River Aire | 21%
|
| 230 | River Great Ouse | 20%
|
| 161 | River Nene | 17%
|
| 145 | River Eden (Cumbria) | 15%
|
| 132 | River Witham | 9%
|
| 112 | River Dee | 5%
|
| 130 | River Teme | 4%
|