Plastinated human corpses posed to look like poker players stand on display at the Body Worlds exhibition on April 27, 2011 in Berlin, Germany. The exhibition, which features human and animal corpses plastinated by Gunther von Hagens, focuses on the role of the heart. It will be open to the public at the Postbahnhof from April 27 to August 14. (Photo by Sean Gallup/Getty Images)

Tourist Police sit in the shade on a road leading to the Coptic Cairo area on May 27, 2011 in Cairo, Egypt. Protests in January and February brought an end to 30 years of autocratic rule by President Hosni Mubarak who will now face trial. Food prices have doubled and youth unemployment stands at 30%. Tourism is yet to return to pre-uprising levels. (Photo by Peter Macdiarmid/Getty Images)

A car stands in water on Ferry Road after two magnitude 6.0 and 5.5 earthquakes struck on June 13, 2011 in Christchurch, New Zealand. The aftershocks have followed four months after the major eathquake which hit the city on February 22, 2011 resulting in the deaths of 181 people. (Photo by Martin Hunter/Getty Images)

Workers at the World's Finest Chocolate company weigh what they hope will be a world record chocolate bar September 13, 2011 in Chicago, Illinois. The candy bar, weighing 12,190 pounds, standing nearly 3 feet high and measuring 21 feet long beat the previous record chocolate bar by more than a ton. (Photo by Scott Olson/Getty Images)

The London 2012 ArcelorMittal Orbit Sculpture at the Olympic park nears completion on November 4, 2011 in London, England. The Ј22 million sculpture designed by Anish Kapoor is nearly complete. Standing at 115 meters tall the permanent structure is Britain's largest artwork and houses an observation deck near the top. (Photo by Peter Macdiarmid/Getty Images)

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)