German fan Didi Senft known as El Diablo cheers as the pack rides past during the 234.5 km seventh stage of the 101st edition of the Tour de France cycling race on July 11, 2014 between Epernay and Nancy, northeastern France. (Photo by Lionel Bonaventure/AFP Photo)

A man wearing a Guy Fawkes mask enjoys a ride on a 350-meter (1148 feet) long water slide during 2015 City Silde Festa in central Seoul, South Korea, July 19, 2015. A 350 meter-long waterslide has been installed in downtown of Seoul, the longest waterslide to be recorded in Korea, according to local media. (Photo by Kim Hong-Ji/Reuters)

Su Daocheng rides his home-made mechanical horse vehicle on a street in Shiyan, Hubei province January 18, 2015. Su spent 2 months making this 1.5 metre high and 2 metre long horse, which weighed 250 kilograms with 4 legs and 2 supportive wheels, local media reported. (Photo by Reuters/Stringer)

People ride a prototype of a driverless vehicle as it is moves through a pedestrian area in Greenwich, east London, February 11, 2015. Britain has begun testing driverless cars in four cities, launching the first official trials ahead of a series of planned rule reviews to accommodate the new technology. (Photo by Suzanne Plunkett/Reuters)

People ride bicycles in Halloween costumes during “Bike Kill 13” in the Brooklyn borough of New York City, October 29, 2016. “Bike Kill” is an annual gathering of builders and riders of home-made bicycles that culminates in a tall bike jousting competition. (Photo by Stephanie Keith/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)

Anti-pollution protesters wearing traditional costumes and contemporary gas masks ride bicycles in the Qingming Grand river park in Kaifeng, Henan Province, China on January 1, 2017. The Beijing Municipal Environmental Protection Bureau extended an “orange alert” for heavy air pollution for three more days. (Photo by SIPA Asia/Rex Features/Shutterstock)