Children of local herders gather at a reindeer camping ground, some 200 km (124 miles) northeast of Naryan-Mar, the administrative centre of Nenets Autonomous Area, far northern Russia, August 2, 2015. People, including local herders and members of their families, gathered at the site to mark Reindeer Day, a professional holiday of reindeer breeding workers, which is celebrated annually on August 2 in the region. (Photo by Sergei Karpukhin/Reuters)

A herder stops for reindeers to have a rest while riding along the tundra area in Nenets Autonomous District, Russia, November 27, 2016. In Russia's remote Arctic regions reindeer herding has been a way of life for centuries. Each winter herders in Russia's sparsely populated Nenets Autonomous District corral their reindeers into open-air pens before selecting weak animals to be culled... (Photo by Sergei Karpukhin/Reuters)

A man climbs up a wooden pole to get a prize during celebration of Maslenitsa, or Pancake Week, a pagan holiday marking the end of winter, near Rumyantsevo, Moscow region, Russia, February 26, 2017. (Photo by Sergei Karpukhin/Reuters)

Brazil's Victoria Chamorro failed to stop the ball during their women's classification 7th-8th place water polo match against China at the 2016 Summer Olympics in Rio de Janeiro, Brazil, Friday, August 19, 2016. (Photo by Sergei Grits/AP Photo)

“Winter shapes, Moscow river”. Moscow river at this part is never covered by ice. When the temperature is very low it's possible to see a strong fog. Morning light and pipes of the oli factory creates a fantastic landscape. Photo location: Moscow, Russia. (Photo and caption by Sergey Rumyantsev/National Geographic Photo Contest)

Spectators await the start of a cinema screening at a Kinostar De Lux Multiplex in the Moscow suburb of Khimki, December 7, 2014. Furniture retailer IKEA has converted one of the cinema halls, completely replacing standard seats with their furniture, according to local media. There are 17 double beds fitted in the hall, which was renamed to “It wakes love”. (Photo by Sergei Karpukhin/Reuters)

A woman argues as Belarus police block a street during an opposition rally in Minsk, Belarus, Saturday, March 25, 2017. Over the past two months, protests have broken out across the country of 9.5 million, sometimes attracting thousands – initially they were focused on the labor law but have grown to encompass calls for the resignation of President Alexander Lukashenko, whom critics call Europe's last dictator. (Photo by Sergei Grits/AP Photo)

Customers clink their cups as they sit in Crazy Toilet Cafe in central Moscow, Russia October 30, 2015. A new Moscow cafe, opened on Friday, serves food to its guests with crockery designed to look like small baths and urinals, in toilet-themed interior with seats resembling toilets, local media reported. (Photo by Sergei Karpukhin/Reuters)