Two of the most densely populated areas of the world are:
1. East Asia: This region includes eastern China, Japan, South Korea, and Taiwan. The presence of fertile river valleys (like the Yangtze and Yellow River), favorable climates for agriculture, and high levels of industrialization contribute to its high population density.
2. South Asia: This region includes India, Pakistan, Bangladesh, and Sri Lanka. High population density is supported by fertile alluvial plains (like the Indo-Gangetic Plain), monsoon agriculture, and a long history of human settlement.