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This fascinating bridge is not only one of London's icons, but also one of the best-known bridges in the world. Its construction started in 1886 and it took only 8 years to finish it. The views from the top are amazing as the towers feature a glass floor walkway. Another sight worth waiting for is to see the bridge open for ships.
If interested, there is an exhibition in the twin towers, dedicated to the history and construction of the bridge. Apart from various short films and interactive displays, you can also see some of the original designs of the bridge. Be sure to check the Victorian engine rooms, too.