Tower Bridge
For the bridge of the same name in California, see Tower Bridge (California).
Tower Bridge is a
bascule bridge in
London, over the
River Thames. It is close to the
Tower of London, which gives it its name. It is sometimes mistakenly called
London Bridge, which is the next bridge upstream. The bridge is owned and maintained by
Bridge House Estates, a charitable trust overseen by the
Corporation of London.
In the second half of the
nineteenth century increased commercial development in the
East End of London led to a requirement for a new river crossing downstream of
London Bridge. A traditional fixed bridge could not be built because it would cut off access to the port facilities situated at that time in the
Pool of London, between
London Bridge and the
Tower of London. A tunnel beneath the Thames, the
Tower Subway, was opened in 1870, but it could only accommodate pedestrian traffic.
A
Special Bridge or Subway Committee was formed in 1876 to find a solution to the river crossing problem. It opened the design of the crossing to public competition. Over 50 designs were submitted, including one from
civil engineer Sir
Joseph Bazalgette. The evaluation of the designs was surrounded by controversy, and it was not until 1884 that a design submitted by
Horace Jones, the City Architect, was approved.
Jones' design was for a
bascule bridge 800 feet (244 m) in length with two towers each 213 feet (65 m) high, built on piers. The central span of 200 feet (61 m) between the towers is split into two equal bascules or leaves, which can be raised to an angle of 83 degrees to allow river traffic to pass. Although each bascule weighs over 1,000 tons, they are counterbalanced to minimise the force required and allow raising in one minute. The original
hydraulic raising mechanism was powered by pressurised water stored in six accumulators. Water was pumped into the accumulators by steam engines. Today the original hydraulic machinery still opens the bridge, however it has been converted to use oil instead of water and electric motors have taken the place of the steam engines and accumulators. The old mechanism is open to the public.
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Tower Bridge under construction, September 28, 1892 |
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Depiction of the construction, inside the bridge |
Construction of the bridge started in 1886 and took 8 years, employing 5 major contractors and 432 construction workers. Two massive piers, containing over 70,000 tons of concrete, were sunk into the river bed to support the construction. Over 11,000 tons of steel provided the framework for the towers and walkways. This was then clad in
Cornish granite and
Portland stone, both to protect the underlying steelwork and to give the bridge a pleasing appearance.
Jones died in 1887, and his chief engineer, Sir
John Wolfe-Barry, took over the project. Wolfe-Barry replaced Jones' original mediaeval style of facade with the more ornate
Victorian gothic style that makes the bridge a distinctive landmark.
The bridge was opened on
30 June,
1894 by the Prince of Wales, the future King
Edward VII of the United Kingdom, and his wife,
Alexandra of Denmark.
 |
Tower Bridge in its river setting, looking east from the viewing platform of The Monument. City Hall is the building shaped like a motorcycle helmet, and below it is HMS Belfast. |
The high-level walkways between the towers gained an unpleasant reputation as a haunt for prostitutes and pickpockets and were closed in 1910. They have now been reopened as part of the Tower Bridge Experience, an exhibition mostly housed in the bridge's twin towers. The exhibition also includes photos, holograms and a film detailing the build, along with access to the original steam engines that once powered the bridge bascules, housed in a building close to the south end of the bridge.
A Behind the Scenes tour can be booked in advance, on which it is possible to see the bridge's command centre where the raising of the bridge is controlled when a vessel passes underneath. The bascules of the bridge are raised around 900 times a year.
Although river traffic is now a fraction of what it used to be, it still takes priority over road traffic. This nearly caused a diplomatic incident in 1996, when the motorcade of
United States President Bill Clinton got stuck on Tower Bridge while the bascules were unexpectedly opened.
The bridge largely replaced
Tower Subway, 400 m to the west, the world's first underground tube railway (1870). Until the bridge was opened, the subway was the shortest way to cross the river from
Tower Hill to
Tooley Street in
Southwark.
A computer system was installed in 2000 to control the raising and lowering of the bascules remotely. Unfortunately this has proved less reliable than desired, resulting in the bridge being stuck in the open or closed positions on a number of occasions (most recently
2 June 2005).
The bridge is near the
Tower of London,
St Katharine Docks, and
Shad Thames.
The north end is near
Tower Hill tube station,
Tower Gateway DLR station and
Fenchurch Street railway station. The south end is about 10 minutes walk away from
London Bridge station.
To the south of Tower Bridge is
Tower Bridge Road which is part of the
London Inner Ring Road.
Gallery
Image:Tower-bridge-south-view.jpg|South view at duskImage:tower.bridge.1.longshotfrom.monument.london.arp.jpg|Distant view, looking east from the MonumentImage:tower.bridge.2.fromonriver.london.arp.jpg|The bridge seen from a river boat, looking upstreamImage:tower.bridge.3.fromsouthbank.london.arp.jpg|From the south bank Image:tower.bridge.4.roadtraffic.london.arp.jpg|The road over the bridge, looking to the Tower of LondonImage:tower.bridge.5.alittleopen.london.arp.jpg|Bridge just opening, looking upstreamImage:tower.bridge.6.veryopen.london.arp.jpg|Bridge openImage:tower.bridge.7.basculecloseup.london.arp.jpg|Close up on fully opened bridge basculesImage:tower.bridge.8.walkwaysexterior.london.arp.jpg|Exterior of high-level walkwaysImage:tower.bridge.9.walkwaysinterior.london.arp.jpg|Interior of high-level walkway (used as an exhibition space)Image:tower.bridge.99.machinery.london.arp.jpg|The Victorian bridge lifting machinery (now disused)
Image:Tower Bridge.JPG|View from the Tower of LondonImage:Tower_bridge_1.jpg|From London Bridge. HMS Belfast (foreground) and fireworks in background. (December 2005)Image:Tower_bridge_2.jpg|From London Bridge. HMS Belfast and the Inner Pool (foreground). (December 2005)Image:Buck palace + change guards 071.jpg|From Southbank, opposite The Tower of LondonImage:Bridge and Dolphin Girl.JPG|Bridge and "Dolphin Girl" sculpture, seen from the northeast*
Crossings of the River Thames*
Official website*
Technical article on the building of Tower Bridge*
BBC News - 17 January 2006 - Fix to stop bridge getting stuck*
Tower Bridge London
