I should clarify: the pollution in Mexico City is particularly bad for a city of its size because of its geography (although it has been getting less worse in t

I should clarify: the pollution in Mexico City is particularly bad for a city of its size because of its geography (although it has been getting less worse in the past decade due to regulation). It's in a valley, trapped by mountains on all sides that basically cooks a toxic stew of smog that sits over the city. Combined with a fairly dry climate, this makes the pollution unusually bad, especially during the more dry winter months. Sometimes you can't see the mountains right outside the city the visibility is so bad. It's more of a long term concern so if you're just planning to stay for a year or two, I think the upsides are greater than the downsides. But I would have serious health concerns about staying and raising a family there. If not for the pollution issue, I would probably have permanently moved there already. It's a world class city.