It's hard to defend the worst scoring city on one of IBM's “driver pain” indexes, but Mexico City is actually doing a remarkable job at reducing the overwhelming gridlock and extreme pollution that once ravaged the city. The introduction of several low emissions transport corridors in addition to expansions to the city's subways and various reforms have had dramatic impacts. The city still needs work, however, but at least the work has started in earnest.

Your likely image of Mexico City traffic is one of immobile gridlock, an intractable smog haze, fire-eaters at traffic lights. It’s true enough — it’s what I saw on a trip there — but it’s out of date. Consider the formula: 18 million people, 6 million cars, and 600 new vehicles hitting the streets every day. Public transit was an unavoidable adventure.

Here's a resident talking about the way public transit used to be: "At peak hours and on weekends between jostles and shouts from mobile vendors, breathing is difficult, but even so, public transportation is something our children should know. It's part of their reality. It's part of their city."

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