The rich love these cities the most:

New York
Hong Kong

Why do the rich love these cities so much? The surface reason:

The ultra-rich value cities that offer "personal safety and security" most, followed by "economic openness" and "social stability" which top "luxury housing" and "excellent educational opportunities."

The underground (real) reason:

Anyone who has recently tried to make their way through the thronged pavements of Piccadilly in London knows there’s another, more important and less politically-correct answer for why certain cities in the West will remain top dogs. The reason is flight capital. The globe’s rich aren’t really moving to London or New York – they are fleeing their home countries and cities.

Any private banker will tell you, that as soon as a centa-millionaire in Moscow, Beijing or São Paolo makes their fortune, the first thing they do is figure out how they can ferret away large chunks of that wealth to countries that guarantee political and personal freedoms, have sound legal systems, a favorable tax environment, good security and good schools for their kids.

We are not just a rich country, but a country for the rich.