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Tower Bridge This is the bridge that most people think of when someone says London Bridge, but in reality the London Bridge is a fairly non-descript bridge further to the west, and in fact was the east most bridge before the Tower Bridge was built. The Tower Bridge gets its name from being very close to the Tower of London. During the design process, one of the goals was to build a bridge that would mesh well with the Tower. The Tower Bridge is also an amazing piece of engineering! It looks much older than it is, and while to the eye it appears to be made of stone, the two towers are actually steel underneath and the stone is just the decorative outside. The need for the bridge came from the fact that the east parts of London had no other bridge and as populations grew public demand grew. There had not previously been a bridge this far east as London was a busy port at the time and the ships could not pass any normal bridge. This became one of the requirements for the Tower Bridge - to allow shipping traffic. There was an open competition for bridge design which was won by Horace Jones and John Wolfe Barry. While this design met the criteria for ship traffic, it also had a creative idea for pedestrian traffic. Each tower was built with a stairway that led up to a walkway that runs between the towers. So even when the bridge is open, it's still possible to get to the other side. Fifteen years later the walkways were closed due to lack of use! Of course today you can take an elevator to the top, but you have to pay. The draw bridge was originally powered by coal engines which fed into an accumulator which stored the energy with which it drove the engines that lifted the bascules (the sides of the draw bridge). Today the engines are powered by oil rather than coal, and electricity is the method of energy transfer rather than steam. The original engines are still on display as part of the exhibit. While the shipping traffic has moved down river, the bridge still gets raised a few times a week. Any boat or ship (of a sufficient size) can request (with 24 hours advanced notice) that the bridge to be raised. While we were there we did not see the bridge being raised, but there is a public schedule available. While it may not be first on your list of activities in London, the bridge exhibition (and walking across the top!) are a very interesting, and short, activity - particularly for the engineering minded. |