It's reassuring to know that you can always get a Coca-Cola wherever you go. Almost anywhere, in fact. According to the BBC, even though this fizzy drink is available almost everywhere, it has yet to (officially) make its way to North Korea or Cuba. This is because these countries are subject to long-term trade embargoes imposed by the United States. 

Some others claim that if you try hard enough, you might be able to get a drink of the stuff—though it will almost certainly be far more expensive than in the United States—and that it will most likely be imported from a neighboring country like Mexico or China.