Participants arrive at the finish line during the annual Maldon Mud Race in Maldon, east England on May 7, 2017. Originating in 1973, the race involves competitors racing around a course through the River Blackwater in Essex at low tide. (Photo by Daniel Leal-Olivas/AFP Photo)

Participants wearing historical costumes ride their high-wheel bicycles during the annual penny farthing race in Prague, Czech Republic November 5, 2016. (Photo by David W. Cerny/Reuters)

A Husky dog looks on before a sled and skijoring race in the village of Kadnikovo outside Yekaterinburg, Russia, December 10, 2016. (Photo by Maxim Shemetov/Reuters)

Pete McLeod of Canada flies in formation with Nigel Lamb of Great Britain, Martin Sonka of the Czech Republic and Kirby Chambliss of the United States during a Recon flight prior to the seventh stage of the Red Bull Air Race World Championship over the Hoover Dam on October 09, 2014 on the border between the U.S. states of Arizona and Nevada. (Photo by Joerg Mitter/Red Bull via Getty Images)

A pet horse tethered on land known as “The Cracker” in Tipton that may be seized by bailiffs on October 10, 2011 in Dudley, England. Horse lovers in Tipton are battling the local council over the tradition of keeping their horses tethered on public land near their homes. Locals say tradition that has been in existence for generations and believe it stems from the age of the canal when many local men used their horses to tow canal barges along the industrial Black Country canals. After a spate of horses running free Sandwell Council are now enforcing the law and impounding tethered horses. Locals are planning their next protest with a horse drive to the council headquarters to try and save their traditions. (Photo by Christopher Furlong/Getty Images)

In this January 7, 2017 photo, Judeley Hans Debel squats down to remove a boot from Tic Tac, holding out his prosthetic leg after his therapeutic riding lesson at the Chateaublond Equestrian Center in Petion-Ville, Haiti. Anne-Rose Schoen, who founded the equestrian center, said perhaps the most important thing about therapeutic riding is it makes youngsters happy in a country where disabled people face enormous challenges. (Photo by Dieu Nalio Chery/AP Photo)

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)

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)