Tower Bridge is not just another bridge crossing the River Thames in London, it is one of the iconic sights that is immediately recognisable throughout the world. Opened in 1894 by the Prince of Wales, later to become King Edward VII, it was built to ease the traffic congestion that was so badly affecting nearby London Bridge. The bridge was designed to be able to allow river traffic through, an economic necessity at the time. Less so now it seems, as when it was built it needed to be opened about 50 times a day, these days it is only opened about 1000 times a year.
The problem facing the City of London Corporation was how to build a much needed bridge in the area without disrupting river traffic. In 1876 a competition was organised and over fifty designs for a bridge were submitted. It was not until eight years later that a design by the then City Architect Horace Jones, in collaboration with John Wolfe Barry, was accepted. It took a total of eight years to build the bridge we can see today. The construction is supported by two huge piers that were sunk into the bed of the river, more than 11,000 tons of steel were used to create the framework for the towers, and the walkways that run between them. The towers were then clad using Cornish granite and Portland stone. The cladding was added for aesthetic purposes only.
When completed, Tower Bridge was the largest bascule bridge ever built. The bascules were operated through the use of hydraulics, powered by steam pumping engines. The created energy was stored in six gigantic accumulators, which ensured that the power was available whenever the bascules needed to be raised. It is possible to raise the bascules to an angle of 86 degrees, which takes about a minute to achieve. When Fully opened, the bridge has a clearance of approximately 42 meters, depending on the height of the tide.
Although Tower Bridge is now powered by oil and electricity, the original steam engines, which are maintained by a dedicated team of engineers, are still in place. Visitors can visit the Victorian Engine Rooms as part of the Tower Bridge Exhibition, here the pumping engines, boilers, and accumulators are magnificently presented in their original setting. Working models allow the visitor to understand the workings of the bridge. There is also a “virtual bridge lift experience” which offers a unique view of the bridge in action.
The bridge was originally painted a dark brown, but in 1977 to celebrate Queen Elizabeth II Silver jubilee, it was painted in the colours of the Union Flag, red white and blue.
In 1910, the high level walkways that were then open to the elements and in part designed to allow pedestrians over the bridge when it was open to river traffic, were closed through lack of use, with Londoners much preferring to wait rather than climb up and then down the stairs. In 1982 the walkways were reopened as part of the Tower Bridge Exhibition. Now fully covered and offering protection from the elements, it gives the visitor the opportunity to take in the panoramic views from a unique vantage point.