The Steintorwall air raid shelter at Hamburg main railway station was built during World War 2 and converted for the cold war in 1969. It was equipped to provide survial for 2702 people for 14 days. Today, it can be toured.
For more info, see the website of the non-profit Hamburger Unterwelten Association: http://www.hamburgerunterwelten.de/Bunker-Hamburg-Hauptbahnhof.html
Hamburg: Second largest city of Germany, situated in the north at the river Elbe, because of the seaport well known as a city of merchants. Because of the nearby sea, you will always have some fresh breeze while you are walking through the streets with nice private town-houses or while you are floating along aboard an “Alsterdampfer” on the river Alster.