Marco Fiera from NoFit State Circus tries out the SkyWire, the new zip wire attraction which opens to the public this week at The Eden Project on July 17, 2012 in St Austell, England. The new 740m zip wire, currently the longest in England, allows the public a bird's eye view of the iconic Rainforest and Mediterranean Biome structures as well as the Cornish attractions outdoor gardens. The Eden Project – which opened in 2001 and has attracted over one million visitors – showcases 100,000 plants from around the world in two giant transparent domes, one of which is the world's largest greenhouse, each recreating different climate conditions. (Photo by Matt Cardy)

“Weapons Instructor”, 2012. It’s a well known fact that the IDF trains some of the best soldiers in the world, but at the source of every good soldier lies an exceptional instructor – and that’s where Cpl. Daniella Stepanoe steps in. She travels from base to base training everyone from paratroopers to elite special forces units in the use of their weapons. (Photo by Israel Defense Forces)

AP photographer Anja Niedringhaus laughs as she attends a swimming event at the 2004 Olympic Games in Athens, August 21, 2004. Niedringhaus, a veteran Associated Press photographer who had covered wars around the world was shot dead and another reporter was wounded on April 4, 2014 when an Afghan policeman opened fire on them in eastern Afghanistan, the news agency said. (Photo by Reuters/Staff)

Men rest after salvaging metal on the 30th floor of the “Tower of David” skyscraper in Caracas February 3, 2014. A 45-storey skyscraper in the center of Venezuela's capital Caracas is a slum, probably the highest in the world. Dubbed the “Tower of David”, the building was intended to be a shining new financial center but was abandoned around 1994 after the death of its developer – banker and horse-breeder David Brillembourg – and the collapse of the financial sector. (Photo by Jorge Silva/Reuters)

An employee in a bookshop adjusts packaged cigarettes which have to be sold in identical olive-brown packets bearing the same typeface and largely covered with graphic health warnings, with the same style of writing so the only identifier of a brand will be the name on the packet, in Sydney on December 1, 2012. A new world-first law forcing tobacco companies to sell cigarettes in identical packets came into effect Saturday in Australia in an effort to strip any glamour from smoking and prevent young people from taking up the habit. (Photo by William West/AFP Photo)

A picture made available on 20 June 2016 shows people praying as they wait to break the fast during the Muslim holy month of Ramadan, in Karachi, Pakistan, 19 June 2016. Muslims around the world celebrate the holy month of Ramadan by praying during the night time and abstaining from eating and drinking during the period between sunrise and sunset. Ramadan is the ninth month in the Islamic calendar and it is believed that the Koran's first verse was revealed during its last 10 nights. (Photo by Shahzaib Akber/EPA)

Humanoid robots compete in a group match of the 20th RoboCup in Leipzig, Germany, June 30, 2016. About 3,500 participants from 45 countries and regions compete in the robot world championship until 04 July. (Photo by Sebastian Willnow/EPA)

Chinese female weightlifter Xiang Yanmei, who competes in the 69 kg weightclass, rests with a weight on her stomach as she checks her phone during a training session in preparation for the Rio Olympics at the Training Center of General Administration of Sports in China on July 20, 2016 in Beijing, China. Xiang Yanmei won the World Championships in 2013 and 2015. (Photo by Kevin Frayer/Getty Images)