Roof-topping enthusiast Daniel Lau takes a selfie with high-rise buildings down below as he stands on the top of a skyscraper in Hong Kong, China on August 15, 2017. A craze that began in Russia has now taken hold in Hong Kong, one of the world's most vertical cities. Mr Lau said he had been inspired by Russian climbers and that he was unafraid of the vertiginous heights he scales. (Photo by ImagineChina/Rex Features/Shutterstock)

Muslims pray at the top of Mount Al-Noor during their Umrah Mawlid al-Nabawi “Birthday of Prophet Mohammad” in the holy city of Mecca, Saudi Arabia January 16, 2016. Muslims believe Prophet Mohammad received the first words of the Koran through Gabriel, at the top of Mount Al-Noor in the holy city of Mecca. (Photo by Amr Abdallah Dalsh/Reuters)

Members of the new BFEplus anti-terror unit of the German federal police holds a G36C automatic weapon after taking part in a capabilities demonstration at a police training facility on December 16, 2015 in Ahrensfelde, Germany. The BFEplus, whose acronym stands for Beweissicherungs und Festnahme Einheit, or Evidence Safeguarding and Arrest Unit, is to support the GSG9 police special forces unit in containing domestic terror threats. Germany is on high-alert following the November Paris terror attacks and a credible threat at the Germany vs. Holland football match in Hanover. (Photo by Sean Gallup/Getty Images)

“Asaro from the Eastern Highlands”. The mudmen could not cover their faces with mud because the people of Papua New Guinea thought that the mud from the Asaro river was poisonous. So instead of covering their faces with this alleged poison, they made masks from pebbles that they heated and water from the waterfall, with unusual designs such as long or very short ears either going down to the chin or sticking up at the top, long joined eyebrows attached to the top of the ears, horns and sideways mouths. (Photo and caption by Jimmy Nelson)

A young boy plays with soap bubbles near Hofburg Palace at Heldenplatz, one of the top tourists attractions in Vienna, Austria, January 26, 2016. (Photo by Christian Bruna/EPA)

Bella Hadid is close to losing her top while on location for a photoshoot in Brooklyn, New York on December 11, 2017. (Photo by NPEx/Splash News and Pictures)

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)

American actress and model Megan Fox stuns in a lace crop top and matching stockings in Manhattan, New York as she strolled to a business meeting on September 12, 2021. (Photo by Rex Features/Shutterstock)