A tourist poses on the glass-bottom bridge at Zhangjiajie Grand Canyon on August 20, 2016 in Zhangjiajie, Hunan Province of China. The Zhangjiajie Grand Canyon's glass-bottomed bridge welcame its trial operation on Saturday and about 8,000 tourists crowded to view the grand glass bridge. (Photo by VCG/VCG via Getty Images)

A photo taken on August 21, 2017 shows girls passing in front of a building with a display of the Soviet state founder Vladimir Lenin Order in Volgograd, Russia. Volgograd Arena will host several cames of the FIFA World Cup 2018. (Photo by Mladen Antonov/AFP Photo)

New program of Munich's Krone Circus performed by two American artists “The Carmenas” during a press conference in Munich, Germany on January 10, 1962, while sitting in a coffee-house. (Photo by Heinrich Sanden Sr./AP Photo)

British holidaymaker Sean Chinn captures a crocodile on camera during a dive at the Jardines de la Reina marine park in Caribbean Sea, Cuba. (Photo by Sean Chinn/Caters News Agency)

Cambridge policemen, known as “Bulldogs”, lined up for the University Bulldogs Chase, dressed in morning coats and top hats, 7th March 1936. (Photo by H. Allen/Topical Press Agency/Getty Images)

A helicopter flies in front of the Wolf Moon as it rises over London, England on January 20, 2019. The Wolf Moon, the Full Moon on January 20-21, 2019, is a Supermoon, making it look bigger and brighter than usual during the total lunar eclipse. (Photo by Dinendra Haria/Rex Features/Shutterstock)

A woman walks past a caricature of Britain's Foreign Secretary Boris Johnson in east London, Britain November 18, 2016. (Photo by Andrew Winning/Reuters)

People search for shells on a beach in Sittwe, Rakhine State, Myanmar, 17 September 2020. International Coastal Cleanup Day is observed annually on the third Saturday of September and will occur on 19 September this year. (Photo by Nyunt Win/EPA/EFE/Rex Features/Shutterstock)