Fireworks explode over the Quadriga statue atop the Brandenburg Gate on New Year's Eve on January 1, 2012 in Berlin, Germany. According to the media, up to one million people celebrate the country's biggest New Year's Eve Party. (Photo by Andreas Rentz/Getty Images)

A baby hippopotamus lies next to its mother on the first day it was presented to the public at the Zoo Berlin zoo on November 1, 2011 in Berlin, Germany. The baby hippo was born at the zoo on October 23. (Photo by Sean Gallup/Getty Images)

A group of scantily-clad women pose for photographs at the annual Venus erotic trade fair in Berlin, Germany on 12 October 2017. Venus Berlin is among the largest international erotic trade fairs, with more then 250 exhibitions from 40 countries and 30,000 visitors. (Photo by Alamy Live News)

Zombie enthiusiasts gather near the broadcast tower at Alexanderplatz before setting out on a “Zombie Walk” in the city center on October 27, 2012 in Berlin, Germany. Approximately 150 zombies, who had organized themselves through Facebook, walked and limped across Alexanderplatz, growled and moaned at passersby and performed their jerking dances. (Photo by Sean Gallup)

Russian soldiers are pictured next to the Reichstag building in this undated photo taken May 1945 in Berlin. Some 70 years on from the Battle for Berlin, instrumental in the end of World War II, Reuters photographer Fabrizio Bensch unearthed pictures by Red Army photographer Georgiy Samsonov, showing his portrayal of a city laid siege. Bensch bought an exactly equivalent FED camera, a Soviet copy of the German-made Leica II, choosing to use black and white film to capture images of the self-same locations he detected his way to in modern-day Berlin. (Photo by Georgiy Samsonov/Reuters/MHM)

An East German civilian (L) shows an East German customs officer the contents of his Trabant (auto) at checkpoint Potsdamer Platz in East Berlin in this November 24, 1989 file picture, as East Germany enforcing stringent customs controls to avoid smuggling. (Photo by Reuters)

Artist Le Pustra and organiser Else Edelstahl pose for a picture at Simon Dach Strasse, a street filled with many bars, in Berlin, Germany, August 28, 2016. Else Edelstahl organises the party series “Boheme Sauvage”, in which people dress up in 1920s style, celebrating Berlin nightlife of a past era. (Photo by Hannibal Hanschke/Reuters)