Will be in Berlin in September. Of the underground tours which are the best? Thanks,
Joan & Augie
Insider Tours do a fantastic 4 hour Berlin walk 'Famous Walk'. Brilliant insight into the history of Berlin past and present. Very good value too.
I believe this tour company has a great reputation for underground tours: http://berliner-unterwelten.de/home.1.1.html Not sure if you have meant going underground tours or underground as in native culture, so here is the other underground: http://www.nativeberlin.com/index.html