Opera singers perform in the pool “AquAria PALAOA” during a rehearsal at the swimming pool Neukoelln on April 27, 2011 in Berlin, Germany. The premiere of the underwater opera AquAria PALAOA is on May 1st. (Photo by Andreas Rentz/Getty Images)

Street fighting in Berlin between Government troops and Spartacists, during the Spartacist uprising which followed Germany's defeat in World War I. (Photo by Keystone/Getty Images). 1919

Egyptian President Hosni Mubarak speaks to the media after talks with German Chancellor Angela Merkel at the Chancellery on April 23, 2008 in Berlin, Germany. (Photo by Sean Gallup/Getty Images)

Farmhand Beatrice Jasiewicz (L) looks on as a colleague carries an injured goose on an open field at the Oekohof Kuhhorst organic farm near Berlin on November 24, 2011 in Kuhhorst, Germany. Goose is the traditional Christmas Eve dinner in Germany. (Photo by Sean Gallup/Getty Images)

Buddy Bears are a series of painted, life-size fibreglass bear sculptures originally developed in Berlin, Germany. The first Buddy Bear was created by the German businesspeople Klaus and Eva Herlitz, in cooperation with the sculptor Roman Strobl in 2001.

Raising a flag over the Reichstag is a historic World War II photograph taken during the Battle of Berlin on 2 May 1945, by Yevgeny Khaldei.

Snake woman Lunga performs on stage during the “Das Goldene Lenkrad” (“The Golden Steering Wheel”) award ceremony on November 5, 2008 in Berlin, Germany. (Photo by Andreas Rentz/Getty Images)