1985 Megacities

In 1985, the world’s megacities—urban areas with populations exceeding 10 million—were rare phenomena, reflecting both rapid urbanization and unique historical trajectories. Tokyo led the list, with its population surpassing 20 million, cementing its status as a global economic powerhouse shaped by post-war reconstruction and technological innovation. New York City, the archetype of the modern metropolis, maintained its megacity status through a long history of immigration and industrialization, though its growth had slowed compared to earlier decades. Mexico City and São Paulo emerged as Latin America’s giants, their explosive growth fueled by rural-to-urban migration and economic centralization, but also challenged by infrastructure strain and informal settlements. Shanghai and Mumbai, while not yet at their later 21st-century sizes, were rapidly expanding due to industrialization and internal migration. These megacities reflected broader trends: while older cities in the developed world saw more stable populations, cities in Asia and Latin America experienced surging growth, setting the stage for the urban explosion that would define the decades to come.

Data from UN World Urbanization Prospects