Explanation

Greenwich is an area in south-east London, England

It lies on the south bank of the River Thames in the historic county of Kent.

It is famous for the Prime Meridian (0° longitude).

It is used as the reference for Greenwich Mean Time (GMT).

Greenwich is famous for calculating the time for all countries.

The Greenwich meridian, also known as the prime meridian, passes through the following countries:

• England
• France
• Spain
• Algeria
• Mali
• Burkina Faso
• Togo
• Ghana 
• Antarctica