St. Paul's Cathedral is a vibrant church and iconic London landmark that is a must see in London! Not only did it hold the jubilee celebrations for Queen Elizabeth II, but it was where Prince Charles and Princess Diana were married! You can go inside for free if you attend a service, or book a sightseeing ticket.
For Harry Potter fans, it houses Hogwart's spiral staircase, though it's not part of a ‘normal’ St Paul’s Cathedral ticket. To see the staircase, be sure to book the Public Trioforum Tour.