On this map we can see the location of the busiest ports in the world. The busiest port is the port of Shanghai. Shipping 647.000.000 tons of goods every year.
What we notice straight away, is the large amount of (busy) ports in east Asia. You can see how crowded the map is around the coastline of Japan, South Korea, China, Taiwan and Hong Kong.
2 other areas that contain a large number of cargo ports close together, are north western Europe and the Gulf Coast of the US.