Take a Yeoman tour, and marvel at the Crown Jewels. A must-see on any trip to London, the Tower Of London has seen over 900 years of British history. Don't miss the collection of armor which is housed in the White Tower, the oldest building at the Tower of London, completed in 1700.The cost is 14.50 pounds, so it is not cheap, but the Yeoman Warder tour is included in the admission and it is not only very informative, but also very funny.
One thing you might find out when you get here is that there is a key ceremony that has been taking place every night at the Tower of London for the past more than 700 years. The only way to be able to partake in it and watch it is if you write a letter to the authorities of the Tower of London two months in advance and express your desire to see this antient ceremony in person, if there is space available, they will reserve it for you. But once you're there, you better get there on time!