Nordbahnhof - And Ghost Stations

So the Nordbanhof is one of the many S- Bahn stations, as well as the U-Bahn, this station is underground,

and during the time of East Berlin, the cold war and the Berlin wall, this became one of the many stations that had then become considered and known as a ghost station until the Berlin wall came down,

these stations were blocked off so that the people in the east could not enter them, and the when the trains going through for the people of the west who may of had to work in the east, were not able to leave the train,

the ghost stations were called ghost stations because they were pitch black, with a few guards scattered around inside.

Nordbahnhof is also close to where the Berlin Wall Memorial is located and also within the station itself, is some information talking about ghost stations.

and there is a  site that gives more of a description of the ghost stations

http://www.berliner-mauer-gedenkstaette.de/en/ghost-stations-558.html