I just don't see it, Mexico is one of the Big 3 on the North American plate and has much more history and culture than the little countries between it and South America. But who am I? Certainly not the United Nations.
And the continent classification system can be a joke (there is NOTHING that separates Europe, Africa and Asia...NOTHING, get out of here with the Suez Canal) but I thought South America and North America had their own plates? In any event, the land expands exponentially upon leaving Panama and going south to Colombia, so it's as good of a transition as any to go from North to South. That said, it can be and in some places is simply known as America just like Europe and Asia can be (and should be) known as Eurasia. The only thing that separates them is culture. And if not for the melting of the land bridge, all of those continents would be merged with America, which is only 100 or so miles from Russia anyways as it is. Then that leads to the question of whether or not Australia is really a continent or not or just a really large Pacific island.
Where was I? Oh yeah, what are your favorite cities on each continent?