These statues mark the official boundaries of the City of London. Note that Queen Victoria is at the centre with a dragon like figure above. If you look at the statue of her in front of Buckingham Palace, an angel is above her, symbolising that only God is above her. In the city of London she does not have the same luck. She can not enter without permission and a ceremony is held each time she enters to welcome her yet remind her that these dragons are guardians of the city's wealth and treasure, and though she is the Queen, she can not take it.