Tower Bridge in London

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Tower Bridge in London

London’s Tower Bridge combines suspension bridge technology on the outer spans that connect the north and south banks of the Thames and uses bascule bridge design for the centre span. Bascule bridges, more commonly referred to as draw bridges, allow for one or two portions of the centre span to lift up, allowing tall boats to pass underneath. The original mechanisms that achieved this function reveal Tower Bridge’s Victorian origins: Coal furnaces powered steam engines that lifted the spans. The steam works were replaced with electric technology in the early 1970s, but the old coal furnace and Victorian steam technology is preserved, and can be viewed on a tour of Tower Bridge.