London was built on top of its streams. The Fleet, the Tyburn, the Westbourne and dozens more were bricked over, piped and turned into sewers as the city grew. This map shows every waterway OpenStreetMap records inside Greater London, 1,297 km of them, split into what still flows in the open and the 228 km that run in culverts and tunnels, with the stories of the rivers that disappeared.
Walk down Farringdon Road and you are walking along the bed of the River Fleet. Stand on the platform at Sloane Square and the River Westbourne passes over your head in an iron pipe. The River Tyburn runs beneath Buckingham Palace. London grew up along a web of streams flowing down from the hills of Hampstead, Highgate and Norwood to the Thames, and as the city spread over them it first used them as open drains, then bricked them over, and finally made them part of Joseph Bazalgette's Victorian sewer system.
Wikipedia's article on the subterranean rivers of London lists 31 of them, 19 north of the Thames and 12 south. OpenStreetMap, the open map of the world that volunteers keep up to date, records many of their courses where they still exist as culverts. I took every river, stream, canal, drain and ditch it maps inside Greater London, measured which parts are marked as running underground, and grouped them into rivers. The map below shows the result: blue where water still flows under the sky, red where it has gone into the dark.
Lines: every OpenStreetMap way tagged as a river, stream, canal, drain or ditch in and around Greater London; paler beyond the boundary. Dashed red with a glow: ways tagged as a culvert or tunnel, as covered, as underground, or drawn below ground level. Gold, with "Highlight the lost rivers": the famous buried rivers listed by Wikipedia. Thin white lines: London boroughs (Natural Earth, generalised). Click any line for its river. Data © OpenStreetMap contributors, ODbL. Base map tiles © Esri; if they do not load the page draws its own outline map.
OpenStreetMap maps 1,297 km of waterway inside Greater London, counting the 75 km of the Thames itself. 228 km of it, 17.6%, is marked as running underground. Leave the Thames out, since almost none of it is buried, and the share rises to 18.6%. That is 142 metres of hidden waterway under every square kilometre of the capital.
Open and buried waterway in Greater London, by type
Kilometres mapped in OpenStreetMap inside the Greater London boundary. Blue: open. Red: in a culvert, pipe or tunnel. Hover or tap a bar.
The small streams have suffered most. Of 510 km of streams and brooks, 30% are buried, and they account for 67% of all the buried length. The big rivers mostly stayed open, because they were too large to cover: only 8.6% of the length tagged as river is underground, and the Thames, the Lea, the Wandle and the Brent still run under the sky for most of their course. Canals (6.0% buried) go underground only in their few tunnels, such as the Regent's Canal under Islington. Drains and ditches, many of them unnamed field drains in the marshes and suburbs, are 15% and 9% buried.
Group the mapped ways by name and 265 named rivers, brooks and channels appear inside Greater London, 79 of them with at least 3 km of mapped line. Of those, 21 run underground for more than half of their length and 4 for all or almost all of it. The Tyburn is buried for every metre of its 12.1 km; the Westbourne for 99% of 12.6 km; the Fleet for 93% of 11.5 km, the open part being the ponds and streams on Hampstead Heath where it rises.
London's most buried rivers
Named waterways with at least 3 km mapped inside Greater London, ranked by the share of their length that is buried (left) or by buried kilometres (right on wide screens, below on phones). Gold names: rivers on Wikipedia's list of subterranean rivers. Click a bar to see the river on the map.
By sheer length of tunnel the leader is not one of the famous central London rivers but the Moselle Brook in Tottenham, with 15.7 km of culvert. Moselle, Westbourne, Tyburn and Fleet together hold 51 km, 22% of all the buried waterway in London. Many of the others are suburban brooks that were piped in the twentieth century as estates were built over them: the Stonebridge and Cholmeley brooks in Haringey, Mutton Brook in Barnet, Saddler's Mill Stream in Enfield and Cran Brook in Redbridge.
The rivers that run under central London have left their names all over the map: Fleet Street, Holborn, Bayswater, Knightsbridge, Peckham, Stamford Brook. These cards tell their stories from their Wikipedia articles, with what OpenStreetMap can still trace of each.
By the middle of the nineteenth century most of these streams were open sewers. The Effra was classed as one below North Brixton by 1821; in 1838 Charles Dickens called Jacob's Island, on the tidal ditches of the Neckinger, the filthiest of the many places hidden in London, and in 1849 the Morning Chronicle called it "the very capital of cholera". Joseph Bazalgette's sewers for the Metropolitan Board of Works then gathered them up. His northern high level sewer took in the Hackney Brook in 1860; the Effra was folded into his southern sewers; the lower Tyburn, Westbourne and Fleet now feed his great interceptors running east to the treatment works at Beckton and Crossness. That is why so many of these rivers survive only as sewers, and why some are not on the map at all.
The thirteen inner London boroughs, counting the City, hold 181 km of mapped waterway outside the Thames, and 37% of it is buried. In the twenty outer boroughs the share is 16%. Per square kilometre, inner London has 221 metres of buried waterway against 124 in outer London. Every mapped metre in the City of London (1.6 km, the Walbrook and the last of the Fleet) is underground; Westminster (74%) and Camden (73%) come next, the Tyburn, Westbourne and Fleet country.
Buried waterway by borough
Share of each borough's mapped waterway that is buried, and the buried length in kilometres. The Thames is left out, because it forms the boundary between boroughs. Purple: inner London. Grey: outer London. Hover or tap a bar; click to zoom to the borough.
The borough with the most buried waterway of all is Haringey, with 34.1 km (62% of its total), thanks to the Moselle and the Muswell, Stonebridge and Cholmeley brooks. Bromley (21.8 km) and Greenwich (20.1 km) follow. At the other end sits Hackney, with just 1.2% of its mapped waterway underground. That is not because Hackney kept its rivers: it is because the Hackney Brook, which once ran right across it, is not mapped at all.
OpenStreetMap maps what volunteers can see or trace, and a river that has become a sewer is hard to trace. Of the 17 lost rivers in the table below, 5 do not appear as waterways in OpenStreetMap at all: the Hackney Brook, the Peck, Earl's Sluice, Stamford Brook and Falcon Brook. They now exist only as sewers, which OpenStreetMap records, when it records them at all, as pipelines rather than waterways. Others are only partly drawn. The Effra, which once drained some 20 square kilometres of south London, appears as just 0.13 km of culvert, and Counter's Creek only as its open tidal mouth, Chelsea Creek (0.5 km). So the buried totals on this page are a floor, not a census: London has much more buried river than the map shows.
The lost rivers, and what OpenStreetMap still maps of them
Rivers named in Wikipedia's "Subterranean rivers of London", with the length mapped inside Greater London and the share of it that is buried. Click a row to see it on the map.
Some of London's buried rivers are coming back up. In the 1960s the Quaggy was put into straight concrete channels to stop it flooding; at Chinbrook Meadows the concrete was torn out and the river given back its meanders, a project finished in 2002. The Ravensbourne has been freed from concrete in Ladywell Fields. In 2009 the Environment Agency, Natural England, the River Restoration Centre and the Greater London Authority set out the London Rivers Action Plan to bring more rivers back to the surface. The Fleet, the Tyburn and the Westbourne are not likely to see the sky again, but their valleys are still there to see in the slope of the streets above them.
Data. OpenStreetMap ways tagged waterway=river, stream, canal, drain or ditch in a box around London (8,439 ways, 2,325 km), downloaded from the Overpass API in 2026. A way counts as buried if it is tagged as a culvert or tunnel (tunnel=culvert, yes, covered, pipe or building passage), as covered, as underground, or with a negative layer and no tunnel=no; everything else counts as open. Lengths are great circle (haversine) distances along each way after clipping it to the Greater London boundary. Ways that share a name ("River Fleet" and "The Fleet") are grouped into one river; unnamed ways (413 km, mostly drains and ditches) are counted in the totals but not as rivers. 17 unnamed ways (19.5 km) drawn as extra channel lines beside the Thames are left out, so that the Thames is not counted twice.
Boundaries. Greater London and its 33 boroughs come from Natural Earth's 1:10m states and provinces, the units whose region is Greater London. These outlines are generalised, so a river running along a borough boundary, as the Fleet does between Camden and Islington and the Westbourne between Westminster and Kensington and Chelsea, can fall wholly on one side. The Thames is left out of the borough figures. Inner London is the statutory definition of the London Government Act 1963.
What this is not. OpenStreetMap is a volunteer map, and its coverage of buried water is uneven: some lost rivers are drawn in full as culverts, some only in part, and some not at all because they are now sewers. Tagging also varies, so a culvert drawn without a tunnel or layer tag counts as open. The stories and dates come from English Wikipedia's articles; where an article does not give a date of culverting, I do not give one either.