Participants ride horses, hold spears and wear historic armoured suits of the Middle Ages as they compete during the Saint George international knight tournament in Moscow, Russia, May 3, 2015. (Photo by Maxim Zmeyev/Reuters)

Students pose for a picture with a 3- D optical illusion artwork of a devastated cityscape in Aleppo, Syria at the campus of the Meiji University in Tokyo on November 18, 2016. The Japanese branch of the human rights organisation Amnesty International displayed the artwork to encourage people to think about the Syrian civil war. (Photo by Toshifumi Kitamura/AFP Photo)

Firework display from the top of the Sky Tower to welcome the New Year on January 1, 2015 in Auckland, New Zealand. (Photo by Dave Rowland/Getty Images)

A woman takes a selfie in front of a Lunar New Year display featuring sheep at a shopping mall in Hong Kong, February 13, 2015. (Photo by Bobby Yip/Reuters)

Jockeys spur buffalos during the Makepung buffalo races at Jembrana in Bali, Indonesia on October 23, 2016. Makepung is a tradition for farmers to celebrate a bumper harvest in Bali. (Photo by Kadek Raharja/Xinhua/Barcroft Images)

A Colombian soldier hugs his girlfriend during the graduation ceremony of soldiers in Nilo, Colombia, February 17, 2017. The soldiers will be deployed to occupy territories formerly controlled by FARC rebels. (Photo by Jaime Saldarriaga/Reuters)

A rescue helicopter is shown at the Mount Everest south base camp in Nepal a day after a huge earthquake-caused avalanche killed at least 17 people, in this photo courtesy of 6summitschallenge.com taken on April 26, 2015 and released on April 27, 2015. Rescue teams, helped by clear weather, used helicopters to airlift scores of people stranded at higher altitudes, two at a time. (Photo by Reuters/6summitschallenge.com)

Cheering The News of Germany's Surrender New Yorkers Gather around a youth wearing a mask of Adolf Hitler to cheer the news of the Surrender of Germany on May 7. The Crowd is gathered in times Square, New York. May 08, 1945. (Photo by New York Post/Photo Archives, LLC via Getty Images)