Tourists look at other festival-goers playing in the mud during the Boryeong Mud Festival at Daecheon beach in Boryeong, about 190 km (118 miles) southwest of Seoul, July 19, 2013. About 2 to 3 million domestic and international tourists visit the beach during the annual mud festival, according to the festival organisers. (Photo by Lee Jae-Won/Reuters)

Barrier tape is tied around 15-month-old Shivani's ankle to prevent her from running away, while her mother Sarta Kalara works at a construction site nearby, in Ahmedabad, India, April 19, 2016. Kalara says she has no option but to tether her daughter Shivani to a stone despite her crying, while she and her husband work for 250 rupees ($3.8) each a shift digging holes for electricity cables in the city of Ahmedabad. (Photo by Amit Dave/Reuters)

A Mongolian wrestler adjusts her hair before a match during the 2016 World Sumo Championship on July 30, 2016 in Ulaanbaatar, Mongolia. (Photo by Taylor Weidman/Getty Images)

The International Garden Photographer of the Year has announced the winner of their Black & White Photo Project 2019. Here: Blue Tit, Criccieth, Wales. (Photo by Alan Price/The International Garden Photographer of the Year)

An American soldier walks ahead of an MKIV (Mark IV) British-made tank, circa 1918. (Photo by Hulton Archive/Getty Images)

King George V inspects the day's kill after a tiger hunt in India during his royal visit to celebrate his accession to the throne. (Photo by Hulton Archive/Getty Images). 1911

US film star Elizabeth Taylor and her first husband Nick Hilton, of the hotelier family, on their wedding day.

Jess Lockwood, of Volberg, Mont., is bucked off Johnny Gringo during bull riding rodeo finals at the Calgary Stampede in Calgary, Alberta, Sunday, July 16, 2017. (Photo by Jeff McIntosh/The Canadian Press via AP Photo)