The Tower Bridge is a bascule bridge over the River Thames in London, situated close to the Tower of London, the medieval fortress of the city.
It was designed by the architect Sir Horace Jones in collaboration with engineer John Wolfe-Barry between 1884 and 1894. The construction of the bridge was necessary due to the expansion of the city and the need for more frequent travel across the Thames after the London Bridge had become too small to serve this purpose alone. However, because it was necessary to maintain the access to the old port, the Pool of London, a hydraulic system which enabled raising the bridge and thus allowing the passing of ships was created.
However, it could be done to cut a conventional bridge navigation and access to now is the old port, the Pool of London, between Tower Bridge and London Bridge, so he designed a hydraulic system to raise when necessary.
It is 244 metres long and has two 65-metre tall towers on each side. In the past it was painted chocolate brown, however today it is painted blue. The original hydraulic mechanism which depended on the power of steam was replaced with the modern hydraulic motors and gearing fuelled by oil rather than water. However, some of the old machinery has been retained and the hydraulic system is open to the public and can be visited by tourists.
Tower Bridge is sometimes confused with its neighbour and mistakenly referred to as London Bridge.