A man prepares his kite to fly during an international kite festival in Alcochete, near Lisbon, Portugal, Sunday, June 28, 2015. Teams from Spain, US, Britain, Italy, France and Portugal performed with their kites during two days on the 13th edition of the event. (Photo by Francisco Seco/AP Photo)

Participants wrestle while riding yaks during Kyrgyz national horse games and festival near the Tulpar-Kul in the Chon Alai range, some 3500 metres (11483 feet) above sea level, Osh region, Kyrgyzstan, July 25, 2015. (Photo by Vladimir Pirogov/Reuters)

Engine driver Josef Kowatsch (top L) steers a train through the NEAT Gotthard Base Tunnel during a media visit near the town of Erstfeld August 24, 2015. Crossing the Alps, the world's longest train tunnel should become operational at the end of 2016, consisting of two parallel single track tunnels, each of a length of 57 km (35 miles). (Photo by Arnd Wiegmann/Reuters)

An arrow-head discovered in 2006 by Archaeologists of the University of Cambridge Archaeological Unit, is displayed by one of the team uncovering Bronze Age wooden houses, preserved in silt, from a quarry near Peterborough, Britain, January 12, 2016. Archaeologists said on Tuesday they had discovered what were believed to be the best-preserved Bronze Age dwellings ever found in Britain, providing an extraordinary insight into prehistoric life from 3,000 years ago. (Photo by Peter Nicholls/Reuters)

An Israeli teenager crawls through mud as he participates in an annual combat fitness training competition, as part of his preparations ahead of his compulsory army service, near Kibbutz Yakum, central Israel February 19, 2016. (Photo by Baz Ratner/Reuters)

An Israeli soldier prays in front of a tank at a military staging area near the border with the Gaza Strip, in this July 24, 2014 file photo. Israel's long-running struggle to balance modern standards with Jewish tradition has come to a head in the military, where new orders curtailing beards among soldiers have met protests from some rabbis. (Photo by Nir Elias/Reuters)

Employees cover bacon on fried dranik, a potato pancake that is the national dish of Belarus, in the Sula History Park near the village of Sula, Belarus March 7, 2016. According to the park's representatives, the two-metre-wide pancake was an attempt to enter the Guinness World Records as the world's largest dranik. (Photo by Vasily Fedosenko/Reuters)

A man covered with thermal blanket walks along railway tracks beside an improvised refugee camp on the border line between Macedonia and Serbia near the northern Macedonian village of Tabanovce, Thursday, March 10, 2016. Around 1.500 migrants and refugees are stranded at Tabanovce transit center for refugees in northern Macedonia. (Photo by Boris Grdanoski/AP Photo)