Luke is right, #20 is Guatemala City.  Knowing the Seabourns might be there bumps it up on the list!

#21.

The country’s largest settlement abroad was Cape Colony, aka Cape Town.  The country is one of the member nations of the Benelux economic union.  This city is the actual seat of government of the country, but not the official capital.  It is also home to all embassies in the country.  Due to Indonesia being one of the country’s former colonies, there is a sizable Indo influence in the city.  The former Bosnian Serb leader, Radovan Karadzic, will be in this city today for his first court appearance.