<P> This is a list of the longest rivers of the United Kingdom . </P> <Table> <Tr> <Th> Rank </Th> <Th> River </Th> <Th> Length (miles) </Th> <Th> Length (km) </Th> <Th> Country </Th> </Tr> <Tr> <Td> </Td> <Td> River Severn </Td> <Td> 220 </Td> <Td> 354 </Td> <Td> Wales / England </Td> </Tr> <Tr> <Td> </Td> <Td> River Thames </Td> <Td> 215 </Td> <Td> 346 </Td> <Td> England </Td> </Tr> <Tr> <Td> </Td> <Td> River Trent </Td> <Td> 185 </Td> <Td> 297 </Td> <Td> England </Td> </Tr> <Tr> <Td> </Td> <Td> River Great Ouse </Td> <Td> 143 </Td> <Td> 230 </Td> <Td> England </Td> </Tr> <Tr> <Td> </Td> <Td> River Wye </Td> <Td> 134 </Td> <Td> 215 </Td> <Td> Wales / England </Td> </Tr> <Tr> <Td> 6 </Td> <Td> River Ure / River Ouse, Yorkshire </Td> <Td> 129 </Td> <Td> 208 </Td> <Td> England </Td> </Tr> <Tr> <Td> 7 </Td> <Td> River Tay </Td> <Td> 117 </Td> <Td> 188 </Td> <Td> Scotland </Td> </Tr> <Tr> <Td> 8 </Td> <Td> River Clyde </Td> <Td> 109 </Td> <Td> 176 </Td> <Td> Scotland </Td> </Tr> <Tr> <Td> 9 </Td> <Td> River Spey </Td> <Td> 107 </Td> <Td> 172 </Td> <Td> Scotland </Td> </Tr> <Tr> <Td> 10 </Td> <Td> River Nene </Td> <Td> 100 </Td> <Td> 161 </Td> <Td> England </Td> </Tr> <Tr> <Td> 11 </Td> <Td> River Bann / Lough Neagh </Td> <Td> 99 </Td> <Td> 159 </Td> <Td> Northern Ireland </Td> </Tr> <Tr> <Td> 12 </Td> <Td> River Tweed </Td> <Td> 96 </Td> <Td> 155 </Td> <Td> Scotland / England </Td> </Tr> <Tr> <Td> 13 </Td> <Td> River Avon, Warwickshire </Td> <Td> 96 </Td> <Td> 154 </Td> <Td> England </Td> </Tr> <Tr> <Td> 14 </Td> <Td> River Eden, Cumbria </Td> <Td> 90 </Td> <Td> 145 </Td> <Td> England </Td> </Tr> <Tr> <Td> 15 </Td> <Td> River Dee, Aberdeenshire </Td> <Td> 87 </Td> <Td> 140 </Td> <Td> Scotland </Td> </Tr> <Tr> <Td> 16 </Td> <Td> River Witham </Td> <Td> 82 </Td> <Td> 132 </Td> <Td> England </Td> </Tr> <Tr> <Td> 17 </Td> <Td> River Teme </Td> <Td> 81 </Td> <Td> 130 </Td> <Td> Wales / England </Td> </Tr> <Tr> <Td> 18 = </Td> <Td> River Don, Aberdeenshire </Td> <Td> 80 </Td> <Td> 129 </Td> <Td> Scotland </Td> </Tr> <Tr> <Td> 18 = </Td> <Td> River Foyle </Td> <Td> 80 </Td> <Td> 129 </Td> <Td> Northern Ireland / Republic of Ireland </Td> </Tr> <Tr> <Td> 20 = </Td> <Td> River Teifi </Td> <Td> 75 </Td> <Td> 122 </Td> <Td> Wales </Td> </Tr> <Tr> <Td> 20 = </Td> <Td> River Tywi </Td> <Td> 75 </Td> <Td> 121 </Td> <Td> Wales </Td> </Tr> <Tr> <Td> 20 = </Td> <Td> River Ribble </Td> <Td> 75 </Td> <Td> 120 </Td> <Td> England </Td> </Tr> <Tr> <Td> 20 = </Td> <Td> River Avon, Bristol </Td> <Td> 75 </Td> <Td> 120 </Td> <Td> England </Td> </Tr> <Tr> <Td> 24 </Td> <Td> River Tyne </Td> <Td> 73 </Td> <Td> 118 </Td> <Td> England </Td> </Tr> <Tr> <Td> 25 </Td> <Td> River Derwent, Yorkshire </Td> <Td> 72 </Td> <Td> 115 </Td> <Td> England </Td> </Tr> <Tr> <Td> 26 = </Td> <Td> River Aire </Td> <Td> 71 </Td> <Td> 114 </Td> <Td> England </Td> </Tr> <Tr> <Td> 26 = </Td> <Td> River Nith </Td> <Td> 71 </Td> <Td> 114 </Td> <Td> Scotland </Td> </Tr> <Tr> <Td> 28 = </Td> <Td> River Tees </Td> <Td> 70 </Td> <Td> 113 </Td> <Td> England </Td> </Tr> <Tr> <Td> 28 = </Td> <Td> River Medway </Td> <Td> 70 </Td> <Td> 113 </Td> <Td> England </Td> </Tr> <Tr> <Td> 28 = </Td> <Td> River Mersey </Td> <Td> 70 </Td> <Td> 113 </Td> <Td> England </Td> </Tr> <Tr> <Td> 31 = </Td> <Td> River Dee, Wales </Td> <Td> 70 </Td> <Td> 112 </Td> <Td> Wales / England </Td> </Tr> <Tr> <Td> 31 = </Td> <Td> River Don, South Yorkshire </Td> <Td> 70 </Td> <Td> 112 </Td> <Td> England </Td> </Tr> </Table> <Tr> <Th> Rank </Th> <Th> River </Th> <Th> Length (miles) </Th> <Th> Length (km) </Th> <Th> Country </Th> </Tr>

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