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A large barge situated at Walbrook Wharf next to the River Thames

The hidden legacy of London's lost rivers

Deep beneath the bustling streets of London lies a murky secret. Buried for more than a century, the hidden rivers of London have seen the city grow for well over 2,000 years.

Image: The outfall of the River Walbrook into the River Thames can be seen just to the left of the barge situated at Walbrook Wharf | Claudine Van Massenhove /

From small native encampments to the first established Roman settlement and all the way up to the vibrant metropolis we see today, these lost rivers have carried with them the history of London - and more than a fair few secrets.

Depending on where you are in the city, it’s more than likely that you’re just a few feet from one of these hidden waterways. There are over 25 submerged rivers, brooks, and streams, snaking across the city and all feeding back into the River Thames. In fact, you might well have walked over many of them without ever having realised that they were there.

So where are these mysterious rivers, and what mysteries do they hold about the story of London? Here are three of London’s hidden rivers and how they shaped the city’s history.

1. River Tyburn

Perhaps one of the most well-known of London’s submerged waterways, there is some debate about where the River Tyburn gets its name. The first theory comes from the ancient Saxon word for boundary stream, which could refer to how ancient Londoners used the river as a boundary line throughout the city. The second theory posits that its name means ‘two burn’, referring instead to its two branches converging in Marylebone before continuing down Oxford Street.

Whatever the origin of its name, the Tyburn flowed through a significant portion of the city and would have been a large part of many Londoner’s lives. Originating from Shepherds Well in Hampstead Heath, the river snakes its way south towards the Thames. Its route passes through Regents Park, where once upon a time, it filled the popular boating lake. From there, it passes through Marylebone, under Oxford Street, Park Lane, and Mayfair, and even right under Buckingham Palace. It’s around this point that the river splits, creating Thorney Island, home of Westminster Abbey, and continues its way through Pimlico until it reaches the Thames.

2. River Fleet

Getting its name from the Anglo-Saxon word for ‘tidal inlet’, the River Fleet is London’s biggest underground river. A substantial waterway, the Fleet was integral to the growth of the city and even lent its name to Fleet Street, which passed over the river just before it met the Thames. It was the site of one of the world’s earliest tidal mills and was used by the Anglo-Saxons as a dock.

Like the Tyburn, the River Fleet originates from two springs in Hampstead Heath and winds south, passing through Camden, Kings Cross, Smithfield, St Paul’s, and joining the Thames at Blackfriars Bridge.

As the city of London grew, the Fleet was used less for travel and shipping and became better known for the filth it carried into the Thames. Used and abused for everything from sewage to industrial waste and even offal, the Fleet was infamous for its stench. Settlements grown on its banks were known for their poor living conditions, and the banks even became home to the torturous Fleet Prison. The quality of the river’s water was so infamously poor that it regularly featured in popular literature of the time, including poetry by Jonathon Swift and Charles Dickens’s Oliver Twist.

Following the Great Fire of London, the river was converted into a canal for industrial use. This proved unpopular, however, and bit by bit the canal was slowly covered over. Today, although well hidden, the river is used as part of London’s sewage system, taking foul water to the Beckton Sewage Treatment Works.

3. River Walbrook

Like the River Tyburn, there are competing theories as to the etymology of the River Walbrook’s name. One theory believes that the name points to the different nations living in London at the time, with the translation of weala broc meaning ‘brook of the foreigners’. Throughout history, London has been home to many cultural groups, ranging from the native Britons to Anglo-Saxons, Romans, and Vikings. Another theory is that it received its name as it ran under the London Wall, a defensive wall built by the Romans.

Originating in Shoreditch, the Walbrook takes an almost direct line straight to the Thames. Flowing under Liverpool Street and Cannon Street, and meeting the Thames just east of Southwark Bridge, the Walbrook was integral to the development of early London.

Dividing the city between Ludgate Hill and Cornhill, the Walbrook is believed to have acted as a boundary line between two settlements in the city. Despite the growth of the city over time, this invisible partition continued between the east and west of the city and was prevalent throughout its history.

In 1838, over 300 human skulls were found on the route of the Walbrook, but this wasn’t the first mention of human heads being found in the river. In fact, it had long been documented that there were a large number of skulls in the riverbed, with one historian noting them as early as 1136. It’s believed that they found their way into the river as a result of a failed uprising against the Roman occupation.