In this Thursday, May 8, 2014 photo, guests look down from the Tilt!, a new tourist attraction that provides guests a unique view of the downtown area from the 94th floor of the John Hancock Building, after it was unveiled in Chicago. People hold onto handrails as the glass and steel facade tilts forward 30 degrees. (Photo by Ashlee Rezin/AP Photo/Sun-Times Media)

Walkers cross the river Waalbrug during the first day of the 98th annual four-days walking event, the “Vierdaagse” in Nijmegen, Netherlands, July 15, 2014. The “Nijmeegse Vierdaagse” is an annual public four-day field march which is held since 1909 in the third week of July. (Photo by Erik van 't Wout/EPA)

Indonesian mahouts clean their Sumatran elephant in a river near the zoo in Medan, North Sumatra, Indonesia, 12 December 2014. According media reports, the smallest of the Asian elephants, Sumatran elephant (Elephas maximus sumatrensis) is facing serious pressures arising from illegal logging and associated habitat loss and fragmentation in Indonesia. The population has come under increasing threat from rapid forest conversion to plantations. (Photo by Dedi Sahputra/EPA)

Miss Australia 2014 Tegan Martin sits down with Miss Universe Chief Photo Editor Francis L. Szelwach to review her photos after posing in swimwear at the 63rd annual Miss Universe pageant in Miami, Florida, in this January 5, 2015 handout photo provided by the Miss Universe Organization. (Photo by Reuters/Miss Universe Organization)

A youth in make-up waits for the start of the annual Zombie walk in Mexico City, Saturday, October 22, 2016. Hundreds dressed in rags and ghoulish makeup to look bloody and decaying, gathered in the historic center of Mexico's capital. (Photo by Christian Palma/AP Photo)

A Kurdish girl wears her relative's assault rifle and ammunition belt as she waits at the Iraqi Kurdish Shaqouli checkpoint, some 35 kilometres east of Mosul, on November 10, 2016. Since the start of the Mosul offensive the Kurds have moved their border some 10 kms closer to Iraq's second city, marking it out with a line in the sand. (Photo by Odd Andersen/AFP Photo)

Spanish soldiers of the 7th Airborne Light Infantry Brigade “Galicia” fire a howitzer Light Gun L118 during maneuvers with other units in preparation to NATO's Very High Readiness Joint Task Force (VJTF) in Zaragoza, Spain, April 19, 2016. (Photo by Javier Cebollada/EPA)

A propaganda troupe perform a flag- waving routine outside the central railway station in Pyongyang, North Korea on September 27, 2017. (Photo by Ed Jones/AFP Photo)