I have started my analysis of how teams might have gotten from Zurich to Berlin. The most obvious way is ot fly from Zurich but which airports might you fly to. Berlin has these airports:
BER Brandenburg
EDBT Allstedt
GWW Gatow (an RAF facility)
SFX Schoenfield
TWF Tempelhof
TXL Tegel
BER Brandenburg--under construction, no fligts land here at this time. Possible opening in 2014 or later.
EDBT Allstedt--no commerical flights since the 1920s when Templehof opened. A research center since then to the 1950s. Berlin's first airport, opened in 1909
GWW Gatow (an RAF facility)--Cold War British zone airfield, closed in 1995
SFX Schoenfield--East German/Soviet Berlin airfield. Operates today and will close when Brandenburg is completed. One runway will be come part of Brandenburg Airport. The Schoenfield terminal will become a German Govt. VIP terminal.
TWF Tempelhof--Cold War American zone airfield, closed in 2008.
TXL Tegel--Cold War French Zone airfield. Operates today, it will close when Brandenburg is opened. It has most of all the commerical flights into Berlin at this time.
There are only two commerical airports in Berlin at present, Tegel and Schoenfield. As apskip stated, only Tegel receives flights from Zurich. Tegel is located in north central Berlin.