Những thành phố đông dân trên Thế Giới.

The Most Crowded Cities in the World! Do you feel like you live in an overcrowded city? Well, if you don't live in one of the following 20, you don't know what crowded means! We've gathered the 20 most crowded cities in the world, with #20 already boasting 12 million souls. Here are the biggest urban centers on earth...