The Great Fire of London.
The City of London is the name of an area of London, where the stock markets are etc. London is a city, but the actual "City of London" is an area between East and Central London. The City of London...
You have answered this yourself in the question ! London.
Made it a better transport city and allowed people to travel. It was also a great break-through for the economical development of London.
London is a city. If you are trying to find out what country it's in; it's in Great Britian.