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The Longest River in the United Kingdom 5

The Longest River in the United Kingdom

Rivers are a natural part of the UK’s beauty and provide many important functions. These rivers vary in size, from small streams to large bodies of water, but they all have an important role to play in British life and scenery. The longest river in the United Kingdom is the Severn River which flows through England and Wales. It runs from its source near Gloucester to its mouth on the Bristol Channel between Cardiff and Weston-Super-Mare

longest river in the united KIngdone

Is the Thames the longest river in the UK?

No, the Thames is not the longest river in the UK. It’s the second-longest river in the British Isles.

Which is the longest river in the United Kingdom?

The longest river in the UK is the Severn.

The Severn River is the longest river in the UK, measuring 220 miles in length. It starts on Mount Plynlimon in Powys, Wales and flows east then northeast to Shrewsbury before turning south through Bewdley and Gloucester towards the Bristol Channel. The river’s mouth is located near the city of Cardiff in South Wales. Plynlimon is the source of three rivers which all spring within a few hundred yards of each other. The three are known as Wales’ shortest, most beautiful, and longest rivers, namely the Rheidol, the Wye and the Severn.

The Severn flows through a number of towns and cities, including Gloucester, Worcester, Cheltenham, Shrewsbury and Bristol. It is navigable for much of its length and was once an important route for transportation. Now, most of the craft on the Severn above Gloucester are recreational. It also provides hydroelectric power to the British national grid. The river is popular for fishing, and it supports a variety of wildlife habitats as well as much of the water for England’s canal system.

Do you know what is the longest river in Europe, and what is the longest river in the world?

10 longest rivers in the UK

River Severn

  • The River Severn is the longest river in Great Britain. 
  • the river carries the biggest volume of water in all of England and Wales.
  • It rises in mid-Wales in the Cambrian Mountains, at 610 m 
  • The river flows through Shropshire, Worcestershire and Gloucestershire before emptying into the Bristol Channel.
River Severn

River Thames

  • The River Thames, known alternatively in parts as the River Isis, is a river that flows through southern England including London. With a length 346 km, the Thames is the longest river in England and the second-longest in the UK. It flows through Oxford (where it is called the Isis), Reading, Henley-on-Thames and Windsor
  • The Thames valley drains the whole of Greater London and a large proportion of of central England
The Longest River in the United Kingdom 6

River Trent

  • The River Trent is the third-longest river in the United Kingdom. 
  • Trent flows through and drains most of the metropolitan central and northern Midlands south and east of its source north of Stoke-on-Trent
  • The river is known for flooding after heavy storms and which in past times often caused the river to change course

River Great Ouse

  • The River Great Ouse is a river in England, flowing through Buckinghamshire, Bedfordshire, Cambridgeshire and Norfolk. 
  • With a length of 230 km, it is the fifth longest river in the United Kingdom. 

River Wye

  • The Wye springs in Wales on Plynlimon, near the source of the severn and borders England, before joining the Severn estuary. It runs though tne beautiful borderlands of south Wales and is important for nature conservation and recreation. Recently however it has become severely polluted by runoff from factory egg and chicken farming and has been the subject of environmental demonstrations.

20 longest major rivers in the UK – Table

RiverLength in milesLength in kmCountry
1 Severn220354Wales and England
4 Great Ouse143230England
5Wye135215Wales and England
6Ure / Ouse129208England
10Tweed96155Border of Scotland
18Bann76122Northern Ireland

Longest UK Rivers

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Ania James

photographer, traveller, mother of twin girls, wife, worldschooler, rulebreaker

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