Originally posted by raven15
Rome, not even a close second.
All other important Western cities in would not have existed as they are without Rome, how could they even be considered?
London, which started as a Roman outpost?
Athens would have been forgotten had the Romans not adapted and forcibly spread their ideas.
All other cities in the area had minor contributions, which likely would have been effectivley accomplished by another city anyhow. No doubt they were very important, but for one reason or another their contributions have not been carried to other times/civilizations intact.
Without Rome, no modern science/technology, which has controlled or been part of every significant event for hundreds of years (though I admit Romans themselves were not great scientists...)
No doubt Chinese cities were large and advanced, but they were too insular to go crusading around the world, they pretty much minded their own affairs (even to this day). Nor has China made any significant contributeions to science, except possibly for the last few years, but that has been Western-based.
Jerusalem has had a minor part in history, mostly it's notable for frequently having it's inhabitants randomly rearranged across several continents, an empty city doesn't have much impact, and anything under development is completely lost, no continuity. Nor have wars for Jerusalem significantly altered history, they have been wars that people fought only when there was nothing more urgent on their minds. Even the crusades only hastened the spread of preexisting ideas.
Nor would Christianity or Islam even have been started with out Rome, given its prominence in Biblical events, and Rome has been the center of Christianity during all of its significant periods.
If you were to remove one city (as with the "remove city" funtion in "Cheat" in Civ2) to make the world totally unrecognizable today, it would be Rome. China would be dominant, and everyone including them would be "pagans" in the dark ages.