Participants in the Grelka Fest at the Sheregesh resort in Tashtagolsky District of Kemerovo Oblast, Russia on April 22, 2017. Russian girls marked the end of the ski season with a record-breaking bikini ski festival at Siberia’s top winter resort, Sheregesh. Some 1,498 skiers and snowboarders undressed to impress in the annual event as they took to the pistes under blues skies and sunshine in a bracing temperature of just 5°C. (Photo by Grelka Fest/The Siberian Times)

Sabera Bayanne, 20, a student of the Shaolin Wushu club, practices in Kabul, Afghanistan January 29, 2017. On a snowy mountaintop to the west of Kabul, a group of Afghan girls practise the flowing movements of Wushu, a sport developed from ancient Chinese kung fu martial arts, stretching and bending and slashing the air with bright swords. (Photo by Mohammad Ismail/Reuters)

Encyclopedia Britannica editions are seen at the New York Public Library on March 14, 2012 in New York City. Encyclopedia Britannica announced it will be ceasing its print edition of reference books for the first time in its 244-year history to focus solely on digital versions. (Photo by Mario Tama/Getty Images)

Ethiopian Orthodox worshippers celebrate the Holy Fire ceremony at the Ethiopian section of the Church of the Holy Sepulcher on April 23, 2011 in Jerusalem's Old City, Israel. Hundreds of Orthodox Christians, all from different sects, participated in the ceremony a day preceding Orthodox Easter, and has been celebrated by worshipers for the last 1,200 years. (Photo by Uriel Sinai/Getty Images)

Pionneers from Aubagne's 1st Foreign Regiment (Legion etrangere) march the Champs-Elysees during the annual Bastille day parade on July 14, 2011 in Paris, France. The French National Day celebrates its revolution in the storming of the Bastille in 1789 through various parades and official ceremonies throughout France. (Photo by Franck Prevel/Getty Images)

Photographer Andy Hall joins the thousands of fans from west Africa who have gathered for Baaba Maal's annual Blues du Fleuve festival in Senegal. Here: Dancers wait to perform on stage. (Photo by Andy Hall/The Observer)

A man jokingly poses with a new installation of British graffiti artist Banksy's art in New York, October 20, 2013. (Photo by Carlo Allegri/Reuters)

A rabbit fails to clear an obstacle during a bunny hop competition at the Old Town Square in Prague, Czech Republic, Monday, April 14, 2014. (Photo by Petr David Josek/AP Photo)