The River Tyburn is a river in London, which runs underground from South Hampstead through St James's Park to meet the River Thames by Whitehall Stairs (near Downing Street and Thorney Street, between Millbank Tower and Thames House). It is not to be confused with the Tyburn Brook which is a tributary of the River Westbourne that is the next Thames tributary to the west on the north bank.
Before it was culverted, the Tyburn rose from the confluence of two tributary streams from the hills of South Hampstead. Its main source is the Shepherd's Well near Fitzjohn's Avenue in Hampstead. Between St James's Park and Buckingham Palace the waters divided to create two distributaries, creating Thorney Island on which Westminster Abbey was built. Enclosed by concrete, bricks, parks and roads the Tyburn flows through underground conduits for its entire length, including one underneath Buckingham Palace and its course has been used for local sewers which connect to the London sewerage system. Marylebone Lane (W1), which defies the grid pattern of streets, follows the course of the Tyburn on what was its left bank through Marylebone village.
From its source at the Shepherd's Well near Fitzjohns Avenue in Hampstead it follows Scholar's Pond Sewer south along Fitzjohns Avenue through South Hampstead (Swiss Cottage) under Avenue Road to Regent's Park. To enter the park's perimeter the Tyburn is carried in an aqueduct over the Regent's Canal then culverted.
The Tyburn gave its name to the former area of Tyburn, a manor of Marylebone, which was recorded in Domesday Book and which stood approximately at the west end of what is now Oxford Street, where from late medieval times until the 18th century traitors were left following hanging. Tyburn gave its name to the predecessors of Oxford Street and Park Lane—Tyburn Road and Tyburn Lane respectively.
Grays Antique Centre near the junction of Oxford Street and Davies Street claims that the body of water which can be seen in an open conduit in the basement of its premises (pictured) is part of the Tyburn; it is undoubtedly close to the culverted course of the stream. From this point the river loosely followed the course of Bruton Lane, Landsdowne Row, the top of Curzon Street, Half Moon Street and across (now under) the southeast path of Green Park to the front gates of Buckingham Palace from where one mouth allegedly used the depression of St James Park Lake to the river and Downing Street, the route to another mouth apparently cut across the present grid layout towards Thorney Street close to Lambeth Bridge, whilst a third route was a 3-metre (9.8 ft) sewer pipe called the King's Scholar's Pond Sewer which issued near Vauxhall Bridge.
- Clayton, Antony. ( 2000) Subterranean City: Beneath the Streets of London. London: Historical Publications. p. 33. ISBN 0948667699
- illustrations 1, 4 of the webpage of the Walbrook River page - a synopsis which cites the following books:
Nicholas Barton, The Lost Rivers of London (1962)
Anthony Clayton, Subterranean City (2000)
Michael Harrison, London Beneath the Pavement (1961)
Alfred Stanley Foord, Springs, Streams, and Spas of London. (1910)
J. G. White, History of The Ward of Walbrook. (1904)
Andrew Duncan, Secret London. (6th Edition, 2009)
- Barton, Nicholas (1962). The lost rivers of London: a study of their effects upon London and Londoners, and the effects of London and Londoners upon them. Historical. ISBN 0-948667-15-X.
- "Grays: The Lost River Tyburn". 2008. Retrieved 18 June 2010.
- "Silent UK – Urban Exploration: River Tyburn". SilentUK.com. 2009. Archived from the original on 3 June 2013. Retrieved 24 August 2016.