Melissa Stewart's team competes in the official restart of the Iditarod, a nearly 1,000 mile (1,610 km) sled dog race across the Alaskan wilderness, in Fairbanks, Alaska, U.S. March 6, 2017. (Photo by Nathaniel Wilder/Reuters)

Ahmed, a 10-year-old jockey, looks on during the opening of the International Camel Racing festival at the Sarabium desert in Ismailia, Egypt, March 21, 2017. (Photo by Amr Abdallah Dalsh/Reuters)

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)

In this July 17, 2015 photo, Michael Chilton squeezes into a corner of his car to make a quick repair to some body panels after he ran into a wall during dirt track racing in the late model division at the Ponderosa Speedway in Junction City, Ky. He banged up the car in the qualifying round and had a few minutes to fix it before the final race. (Photo by David Stephenson/AP Photo)

The beard of a skater, one out of some 1,100 athletes, is covered with ice and snow during the 200 km (124 miles) speed skating race in the Carinthian village of Techendorf January 30, 2015. Techendorf is hosting the Alternatieve Elfstedentocht Weissensee (Alternative Eleven City Races Weissensee) races, a traditional Dutch series of speed skating events for both professionals and amateurs with some 5,000 participants, until January 31, 2015. (Photo by Leonhard Foeger/Reuters)

Every year, in the Rostov region of Russia, a group of 40 young and not so young rural workers compete in the Bison Track Show, or more affectionately known as: Russian Flying Tractor Racing. In front of crowds numbering up to 30,000 people, a series of smoke spilling, monstrous farming machines tear round an 8km mud track, plowing through lakes and dirt mounds, their turbos screaming and tyres scrabbling to find grip.

“Greyhound racing is a popular sport in Great Britain with attendances at around 3.2 million at over 5,750 meetings, across 26 stadia in 2007 alone. There are 25 licensed stadia in Britain, it is a Parimutuel betting tote system with on-course and off-course betting available, with a turnover of £75,100,000”. – Wikipedia

Photo: Pevensy Bugsy (L) wins the 8th race from Blanemore Razl (R) at the Coral Brighton and Hove Greyhound Stadium on March 21, 2012 in Brighton, England. (Photo by Mike Hewitt/Getty Images)

Britain's Chris Froome, wearing the overall leader's yellow jersey, is followed by Spain's Alberto Losada, Italy's Vincenzo Nibali and Spain's Alejandro Valverde as they speed downhill during the seventeenth stage of the Tour de France cycling race over 161 kilometers (100 miles) with start in Digne-les-Bains and finish in Pra Loup, France, Wednesday, July 22, 2015. (Photo by Christophe Ena/AP Photo)