Hamburg, originated in Hamburg, is a castle built on the banks of the Elbe River in 825 BC. Now the castle no longer exists, only on the Hamburg emblem can we see the original castle. Hamburg is the second largest city in Germany after Berlin, but many people do not know that it is also one of the world's famous "water cities" with more than 2300 bridges, more than the number of bridges in Venice and the largest number of bridges in Europe. Hamburger Harbour is an important international water hub. When ocean-going ships from all over the world come to Germany, they will berth in Hamburg Harbour. So Hamburg is called "the gate of Germany to the world".