Yes, an unusual question

More like Paris in terms of architecture and city planning and café culture, Vienna is also roughly the same size as Paris.

London is about 4 times bigger than both and more cosmopolitan

I agree. Has more of a Paris feel.

Thanks, that is what I needed to know

Paris is bigger than London. Paris and Vienna are both continental European towns, and that makes a difference from London. In the 19th century every city in Europe apart from London was trying to be like Paris, and you do see that.

Vienna is unique - completely unique.

London and Paris are too.

If I had to choose which Vienna is more like I'd go for Paris, but they really are not at all similar....

Vienna is more like Wien than any other place; and they speak better Engkish than people in London do. But, yes, Vienna and Paris both have have a uniform architectural style, generally restored to museum quality and repeated over and over and over again.

I agree with all the others - London is very different from Paris and Vienna. I have to admit that London is my favorite of the three.

Nature rsp. the National Park in and arround Vienna is unique. But agree in some points I would say a bit more Paris than London.

London is the exception among the three. Vienna is like Paris...historically, culturally.

I've been back to all three numerous times. Simply because all three appeal to me.

Paris is, however, the one I like best.

Actually Wengen London is much bigger than Paris, at least people wise.

Vienna is more like Wien than any other place;

@Mister E
I fully agree. :-) :-)