A passenger waits after his train arrived in Nouadhibou, Mauritania’s second largest city and the main export port for the country’s iron ore industry, on June 25, 2014. The mining company’s employees proudly call their firm the lung of their nation's economy and the train that ferries the ore to the coast stretches some two kilometres, making it one of the world's longest. SNIM mines black iron ore in the northern town of Zouerate, a remote desert location which nevertheless attracts people from all over the country looking for work. (Photo by Joe Penney/Reuters)

Young Chinese football players help an injured player off the field during training at the Evergrande International Football School on June 12, 2014 near Qingyuan in Guangdong Province, China. The sprawling 167-acre campus is the brainchild of property tycoon Xu Jiayin, whose ambition is to train a generation of young athletes to establish China as a football powerhouse. The school is considered the largest football academy in the world with 2400 students, more than 50 pitches and a squad of Spanish coaches through a partnership with Real Madrid. (Photo by Kevin Frayer/Getty Images)

Local villagers ride a local coal powered steam train on March 27, 2015 at a station in the town of Shixi , Sichuan Province, in Southern China. While China boasts the world's most extensive high-speed rail infrastructure with over 16,000 kilometers of track, the Shixi-Bagou railway is still a primary connection for local villagers between towns and is kept alive by tourist cars carrying passengers for ten times the price. The rail line came into service in the late 1950s and the train was initially used to transport coal from a now-shuttered mine before passenger carriages were added. (Photo by Kevin Frayer/Getty Images)

16-year-old panda, Ye Ye, rests in an enclosure at the Wolong Nature Reserve, a conservation center that trains pandas for release into the wild. This image was published in the August 2016 National Geographic magazine as part of the “Pandas Gone Wild” story. (Photo by Ami Vitale/National Geographic Creative)

Elvis Presley impersonator Sean Wright poses next to the Elvis Express train at Sydney's Central station before it departs for the 26th annual Elvis Festival being held in the New South Wales town of Parkes in Australia, January 11, 2018. (Photo by Daniel Munoz/Reuters)

A U.S. Army crew chief flying on board a CH-47F Chinook helicopter observes the successful test of flares during a training flight in Afghanistan, March 14, 2018. (Photo by Tech. Sgt. Gregory Brook/Reuters/U.S. Air Force)

Leon Feingold, right, drops his jeans as his girlfriend Patrizia Calvio looks in her purse on the uptown E Train during the 18th annual No Pants Subway Ride, January 13, 2019, in New York. (Photo by Kathy Willens/AP Photo)

Shepherd brothers Mustafa Erbay and Baran Erbay train their camels on snowy grounds, enabling them to become champions in competitions held in the Aegean and Mediterranean regions in Baskale district of Van, Turkey on February 1, 2020. (Photo by Ozkan Bilgin/Anadolu Agency via Getty Images)