Which are the most populous cities?
The 21st century seems to mark the start of a definite trend that will see the world's population become more and more urban.
The latest figures and analysis released by the United Nations point to increased urbanisation in developing countries.
The main mega-cities remain in the top, with the 10 million inhabitants figure as a benchmark.
Click on the links below to view the time in any 'megalopolis' or its country.
You can also view time several cities with an animated timepiece, City Time .