Berliner Unterwelten e.V. - Berlin Underground Society
For questions on subterranean constructions, you can get competent information from the Verein Berliner Unterwelten e.V. (an organization for underground preservation), which was founded in the spring 1999. It's the organization's business to investigate, document and do whatever possible to preserve subterranean constructions of historical value.
Members of the organization organize tours on a regular basis and give advice to businesses, governmental institutions and the press on questions about the different constructions.
For permissions for tunnel access and film shoots please ask the civil engineering department in question.
In addition, please contact the Verein Berliner Unterwelten e. V. to get information about the location owner who has to give its approval for a specific set location.