Cities are pushing beyond their limits and are merging into new massive conurbations known as mega-regions, which are linked both physically and economically. Their expansion drives economic growth but also leads to urban sprawl, rising inequalities and urban unrest.
The biggest mega-regions, which are at the forefront of the rapid urbanisation sweeping the world, are:
- Hong Kong-Shenhzen-Guangzhou, China, home to about 120 million people;
- Nagoya-Osaka-Kyoto-Kobe, Japan, expected to grow to 60 million people by 2015;
- Rio de Janeiro-São Paulo region with 43 million people in Brazil.