Which 3 capital cities are the only ones without any letters that can be filled in?

Question

I have heard that there are 3 capital cities that have no letters that can be filled in (filled in letters being a b d g etc; so when you write them there is a complete circle that can be filled in).

I know one of them is Vilnius, the capital of Lithuania, but does anyone know the other two?

Also, the first letter is capital but the rest are lower case - so there is no confusion between letters such as G/g

Answer 1

Minsk - capital of Belarus, Tunis - capital of Tunisia

There also is Nuuk, capital of Greenland:

http://en.wikipedia.org/wiki/Nuuk