As part of an Architectural study tour in November 1996, I photographed an area of Berlin where the wall had been taken down. The intention was to record the traces of a Borderland between east and west through photomontage. This borderland was the void left behind by the recently removed wall. There were many and varied architectural projects seeking to fill that void.
The river Spree is also seen as a void in the city.
There was also Daniel Libeskind's Jewish Museum (under construction during our visit) which created voids as memorials.
* "Many saw the void left by the dismantled wall in Berlin's middle as a scar that might never heal, either architecturally or historically. Historically, of course, this space never was a centre. Instead it marked the boundary between the old Berlin, east of Brandenburg Gate, and its western expansion through the Tiergarten district and beyond."
A feature in the city at the time was the services temporarily above ground being piped around the city. This contrasted with all services being concealed (in other voids) in Libeskind's Museum.