Only three per cent of the world’s population lived in cities in 1800s, but that number will swell to 70% by 2050. Cities in Asia underwent rapid growth in the past century, and “Four Great Cities of Asia” examines the remarkable evolution of the mega-city. From the world’s largest city, Tokyo, to the colorful chaos of Delhi, and from the modern miracle of Seoul to the teeming streets of Bangkok, “Four Great Cities of Asia” is a passport to the high-tech marvels and back-street secrets of four of the world’s most amazing cities.