31 interesting facts about the River Thames

River Thames London

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Most people know the River Thames as a major landmark that cuts through the center of London. However, there’s so much more to this historic river than you’ll learn from a river cruise past the London Eye and Houses of Parliament. In fact, after a lot of research, I discovered a whole wealth of fascinating and sometimes pretty unusual facts about the River Thames I bet most of you didn’t know either. Here are 31 of my favourites…


31 interesting facts about the River Thames


The River Thames is the longest river in England

1. While many associate the Thames as being only in London, the river actually stretches 346 km (215 miles) across the south of England.

2. However, it is only the second-longest river in the United Kingdom, being beaten just slightly by the River Severn which runs through England and Wales at 354 km (220 miles) long.

3. The River Thames travels through Gloucestershire, Wiltshire, Oxfordshire, Berkshire, Buckinghamshire, Surrey, London, Kent and Essex, before flowing into the North Sea via the Thames Estuary.

4. In parts, mainly around Oxfordshire, the Thames is also sometimes called the Isis. Historians believe the name Isis is simply a shortened version of Tamesis, the Latin name for the Thames.


There are over 200 bridges crossing the Thames

Shard and Tower Bridge London

Tower Bridge in London

5. There are over 200 bridges spanning the length of the River Thames.

6. The oldest surviving bridge over the Thames is New Bridge in Oxfordshire which dates back to the 13-century and is now a Grade I & II listed structure.

7. 35 of the Thames bridges can be found in London.

8. The oldest surviving bridge over the Thames in London is Richmond Bridge which dates back to 1777.

9. London’s iconic Tower Bridge is the only drawbridge on the Thames that can be opened using an electro-hydraulic system to allow river traffic to travel through. The bridge is raised around 1,000 times a year.

10. In the 1960s, an American oil tycoon named Robert McCulloch purchased London Bridge for $2.5 million. The bridge can now be found in Arizona’s Lake Havasu. There are rumors that McCulloch thought he was buying Tower Bridge, however, this has since been discredited. Turns out he was just a bit eccentric!

11. Due to the width of the river the closer it gets to the Thames Estuary, the Dartford Crossing is the only place you can cross the Thames by road between London and the sea. The crossing used to be just two tunnels until the Queen Elizabeth II Bridge was built in 1991 – now the longest bridge to cross the Thames.


The Thames Tunnel was the world’s first underwater tunnel

Greenwich Foot Tunnel

Greenwich Foot Tunnel

12. Built in 1843, the Thames Tunnel was the world’s first underwater tunnel and was originally built for horse-drawn carriages. The tunnel connects Rotherhithe and Wapping in London. In 1869 it was converted into a railway tunnel for the East London Line, which is now part of the London Overground.

13. There are only three railway bridges crossing the Thames in central London, the rest of the rail network runs through tunnels underneath the river.

14. There are only two fully pedestrianised foot tunnels running underneath the River Thames in London; Greenwich Foot Tunnel and Woolwich Foot Tunnel.

15. The 120-year-old Greenwich Foot Tunnel is said to be haunted by the ghosts of a Victorian man and woman who supposedly can be spotted late at night and their footsteps heard echoing in the tunnel.


There are around 100 islands along the River Thames

16. While the definition of what constitutes an island on the Thames is often disputed, there are currently around 100 recognised islands or small eyots along the River Thames.

17. Around 45 of the islands on the Thames are inhabited. In fact, you can read about the fascinating histories and residents of many of the Thames Islands in the book ‘Carl Goes London Islands‘.

18. The largest inhabited island on the London stretch of the River Thames is Eel Pie Island in Twickenham. Known for its Eel Pies (unsurprisingly!), the island has around 50 homes, numerous artist studios, three boatyards and a rowing club. It was also once home to the Eel Pie Island Hotel, a famous music venue where the likes of The Rolling Stones, The Who, Pink Floyd and David Bowie all played in the 1950s and 60s. You can even now visit the Eel Pie Island Museum.

19. The Magna Carter was signed by King John in 1215 on an island on the Thames near Windsor, which is now fittingly known as Magna Carter Island.


The Thames Barrier is the second-largest movable flood barrier in the world

Boat on the River Thames

Boat approaching the Thames Barrier in London

20. The Thames Barrier was designed to protect Greater London from flooding caused by high tides and storm surges moving up from the North Sea. It is the second-largest barrier in the world after the Oosterscheldekering in the Netherlands.

21. The Barrier was originally only designed to last until the 2030s. Careful maintenance could see it last longer, however, the barrier is being regularly monitored and future plans are already being drawn up.


2/3 of London’s drinking water comes from the Thames

22. Two-thirds of London’s drinking water comes from the Thames – it’s thoroughly treated first though so don’t go drinking directly from the river!


The Thames is one of the cleanest rivers in the world… but this certainly wasn’t always the case

23. The Great Stink took place in the summer of 1858 when the large amounts of sewage in the Thames combined with the hot weather lead to a terrible stench across the city. The smell was so bad that much of the capital came to a complete standstill, which included parliament being suspended.

24. In 1957 the Thames was declared ‘biologically dead’ by the Natural History Museum due to the amount of sewage and pollution not allowing anything to live within it.

25. 60 years on, the Thames is now one of the cleanest rivers in the world to flow through a major city, with hundreds of species of fish, mammals and invertebrates once again calling the river and riverbeds home, including seals, porpoises and even the occasional dolphin.

26. Although, it’s estimated that one dead body a week is recovered from the Thames.


There are over 200 rowing clubs on the Thames

Person rowing in River Thames

27. Many watersports take place on the River Thames, among the most prevalent of these being rowing, with over 200 rowing clubs along the river.

28. One of the most important rowing events to take place in the Thames is the annual Oxford v Cambridge Boat Race which has seen the two universities complete on a stretch of the river in London since 1829.

29. Day’s Lock on the River Thames in Oxfordshire used to be home to the annual World Poohsticks Championships – and yes I am referring to the game invented by A. A. Milne in his Winnie the Pooh children’s books. However, in 2015, the championships were moved elsewhere.


‘Frost Fairs’ used to take place on the frozen river in winter

30. Up until 1814, extremely cold winters would cause the River Thames to completely freeze over and people would take to the frozen river for ‘frost fairs’. These fairs included vendors selling their wares, plenty of food and drink, and activities including dancing, bowling, skating and more.

31. King Henry VIII once travelled from central London to Greenwich by sleigh along the river when it froze over in 1536 – I think this is one of my favourite River Thames facts!


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London City Calling

Emily is a born and raised London girl, starting life in the north of the capital then moving down to Fulham in the southwest. She has a master’s degree in Social and Cultural Anthropology from University College London and now works full-time running this blog and as a freelance travel writer, splitting her life between London and travelling the world as a digital nomad.

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