A man sits waiting for a train on the London Underground in 1890, when the platform floors were still made from wooden floorboards. (Photo by Hi-Story/Alamy Stock Photo)

A man enters an adult amusement establishment in Shinjuku's nightlife district of Kabukicho in Tokyo, August 27, 2015. (Photo by Thomas Peter/Reuters)

Philippine President Rodrigo Duterte looks at Miss Universe candidates at the presidential palace in Manila, Philippines January 23, 2017. (Photo by Erik De Castro/Reuters)

The waning moon is setting over the mountain “Les Cornettes de Bise” located at the border of the Haute-Savoie and the Valais canton of Switzerland in the Chablais Alps, photographed from Glutieres, January 7, 2015. (Photo by Anthony Anex/EPA)

A long exposure image of embers flying off burnt out trees following the wind driven wildfire ranging in the mountain area near Rancho Cucamonga late 30 April 2014. Earlier in the day more than 1,500 homes were evacuated as the Etiwanda fire charred around 1,000 acres in San Barnardino National Forest. (Photo by Stuart Palley/EPA)

“Kids of Sapa”. Four little beautiful Hmong girls from Lao Chai Village, near Sapa, Vietnam. (Photo and caption by Felipe Hanower/National Geographic Traveler Photo Contest)

“When I was 8 years old, my parents paid a smuggler to take me across the Himalayas, a weekslong walk over the mountains from Tibet to India. It was a trek that tens of thousands of other Tibetans have taken since the Dalai Lama fled a failed 1959 uprising against Chinese rule. My parents must have had their reasons to send me here; they must have had the best of intentions. But 18 years later, I still don't know why they did it. They are not political people. They are small farmers who raise barley and a few yak in a rural area not far from Lhasa, the Tibetan capital. I have not seen them since I left...”. – Tsering Topgyal via The Associated Press. (Photo by Tsering Topgyal/AP Photo)

Germany's Wolfgang Kimmig-Liebe, who has been volunteering as Santa Claus for years, is searched by a Carabiniere paramilitary police officer before entering in St. Peter's Square at the Vatican to attend Pope Francis general audience, Wednesday, December 2, 2015. (Photo by Alessandra Tarantino/AP Photo)