London has the most billionaires of all the cities in the world!

http://www.independent.co.uk/news/uk/uk-has-the-most-billionaires-per-population-than-any-other-nation-in-the-world-9350471.html

London has the highest number of billionaires than any other city in the world- 72 of them.
The UK as a whole has 104 billionaires.

The highest ranked Brit is the Duke of Westminster who owns lots of property in central London, other Brits on the list include Sir Philip Green, Sir Richard Branson and Mike Ashley of Sports Direct.