The Tokyo Area, including Chiba, Kanagawa, and Saitama, is the most populous metropolitan area in the world with a population of over 35 million people. Tokyo is also the most expensive city in the world. | The Tokyo Area, including Chiba, Kanagawa, and Saitama, is the most populous metropolitan area in the world with a population of over 35 million people. Tokyo is also the most expensive city in the world. |