Hong Kong, officially the Hong Kong Special Administrative Region of the People's Republic of China, is a metropolitan area and special administrative region of the People's Republic of China on the eastern Pearl River Delta of the South China Sea. With over 7.5 million residents of various nationalities in a 1,104-square-kilometre (426 sq mi) territory, Hong Kong is one of the most densely populated places in the world.

Mumbai, formerly known as Bombay, the official name until 1995) is the capital city of the Indian state of Maharashtra. According to the United Nations, as of 2018, Mumbai is the second-most populous city in the country after Delhi and the seventh-most populous city in the world with a population of roughly 20 million.