Changing of the Guards at the Tower of London 

Did you also think that the changing of the guards was only a formal spectacle that happens at Buckingham Palace? What a cool thing to see! Anna lived in London for 2 years and never saw any guard change ceremony.
Since they change their shifts every 2 hours, and the fact that you can easily spend a whole day at the Tower of London and still not see everything, I think your odds of seeing this are pretty high.
People often confuse Tower Bridge and London Bridge. Tower Bridge, which towers majestically over the River Thames right next to this ancient landmark, is well worth visiting if you are in London next.
We ended up chatting to one of the Beefeaters names Gary, and he is one of the funniest guys we've ever met. Although you won't get a response out of the guards in this video when they're on duty, have a chat with the Beefeaters at the Tower who are more than happy to talk, share stories, and point countless people towards the toilets.