A participant jumps on vintage skis during a traditional historical ski race in the northern Bohemian town of Smrzovka, Czech Republic, February 20, 2016. (Photo by David W. Cerny/Reuters)
A Tibetan rider fires his weapon as he perfoms his riding skills at the Qinghai Yushu Horse Racing Festival on July 27, 2007 in Yushu County of Yushu Tibetan Autonomous Prefecture, Qinghai Province, northwest China. The Horse Racing Festival of Tibetan nomads in Yushu Prefecture falls in late July and early August on the Tibetan calendar. During the festival, various equestrian skills will be performed along with singing, dancing and costume shows. (Photo by China Photos/Getty Images)
In this Friday, March 13, 2015, Mitch Seavey's lead dogs with frosty whiskers at the Huslia, Alaska, checkpoint for the Iditarod Trail Sled Dog Race. (Photo by Loren Holmes/AP Photo/Alaska Dispatch News)
The Mexican ship Cuauhtemoc is pictured during the Tall Ships Races 2016 parade, in Lisbon, Portugal, July 25, 2016. The Tall Ships' Races are races for sail training “tall ships” (sailing ships). The races are designed to encourage international friendship and training for young people in the art of sailing. The races are held annually in European waters and consists of two racing legs of several hundred nautical miles, and a “cruise in company” between the legs. Over one half (fifty-percent) of the crew of each ship participating in the races must consist of young people. (Photo by Pedro Nunes/Reuters)
A bride stretches before the event during the “Running of the Brides” race, in Bangkok, Thailand, December 2, 2017. Six hundred of to be brides and their grooms compete a run race aimed to win more than two million baht (61,000 US dollars or 51,000 euro) of wedding package prizes including a pair of white gold diamond rings and honeymoon trip to the Maldives. (Photo by Athit Perawongmetha/Reuters)
A competitor tries to clear a jump during the RHL Beach Race at Weston-Super-Mare on October 9, 2011 in Weston-Super-Mare, England. (Photo by Richard Heathcote/Getty Images)
This computer image provided Monday March 17, 2014 by the Press Office of socialist candidate to Paris Mayor Anne Hidalgo, shows a tunnel of abandoned railway from the 19th century, now ramshackle and overgrown, turned into a cinema. Hidalgo’s plan envisions not just a green space but in the tunnels, places for farming fish and mushrooms. (Photo by AP Photo/Anne Hidalgo's Press Office)
In this photo provided by Andreas Langreiter via Global-Newsroom, Hannes Arch of Austria performs during the finals of the first stage of the Red Bull Air Race World Championship in Abu Dhabi, United Arab Emirates, Saturday, February 14, 2015. (Photo by Andreas Langreiter/AP Photo/Global-Newsroom)