A 20 metre high spiral staircase in a tower used as an emergency exit, is seen inside a Federal Reserve bank (Bundesbank) bunker, prior to the bunker's official opening to the public in Cochem, Germany, March 18, 2016. West Germany's Central Bank (Deutsche Bundesbank) stored some 20 billion German marks of emergency notes in two underground bunkers, one in Frankfurt the other in Cochem, between 1964-1988 during the cold war. (Photo by Kai Pfaffenbach/Reuters)

In a picture taken with an underwater camera, a couple stands in front of a Polynesian priest during their underwater wedding ceremony on October 25, 2014 in Bora-Bora, in French Polynesia. The ceremony lasts twenty minutes and costs around 2700 euros. (Photo by Ben Thouard/AFP Photo)

Elephants munch on Christmas trees in their enclosure at Berlin's Zoologischer Garten Zoo on January 4, 2013 in Berlin, Germany. Traditionally, the animals get in the first week of the year leftover Christmas trees. (Photo by Andreas Rentz)

Bikini-clad women sit as they operate a 3.6 metre-high custom-made female robot at the “Robot Restaurant” in Kabukicho, one of Tokyo's best known red light districts, August 15, 2012. (Photo by Tokyo Scum Brigade)

Waves crash over lava as it flows into the ocean near Volcanoes National Park in Kalapana, Hawaii on November 27, 2012. A volcano on Hawaii's largest island is spilling lava into the ocean, creating a rare and spectacular fusion of steam and waves that officials said on Tuesday could attract thrill seeking visitors if it continues. (Photo by Hugh Gentry/Reuters)

Russian honor guard soldiers warm up prior a rehearsal for the Victory Day military parade in St. Petersburg, Russia, Wednesday, May 3, 2017. The parade will take place at Dvortsovaya (Palace) Square on May 9, to celebrate 72 years after the victory in WWII. (Photo by Dmitri Lovetsky/AP Photo)

Participants take part in the annual New Year' s Day Parade in central London, United Kingdom on January 1, 2018. Reports state that 8,000 performers representing the London boroughs and countries from across the globe are parading along the streets of London's West End on New Year’s Day. (Photo by Tolga Akmen/AFP Photo)

A woman reacts with flour over her face while playing a game with cake-making ingredients as part of local festivities marking Myanmar's 70th Independence Day in Yangon on January 4, 2018. The country is celebrating the 70th anniversary of its declaration of independence from British colonial rule. (Photo by Ye Aung Thu/AFP Photo)