The giant metal structure sits 330ft above the ground on the roof of a 22 storey office block in Dutch capital Amsterdam on September 6, 2016. Tourists sit in a playground-style chair as they propel themselves them over the edge of the building with only thin-air between them and the ground below. Engineers spent several years designing and building the breathtaking swing. By being fixed to the top of a building it reaches new heights – dwarfing other swings around Europe but trailing behind the 1,150ft high mechanical rides at the Stratosphere Hotel in Las Vegas, Nevada. (Photo by Huub Zeeman/SWNS.com)

Elementary school children play outside their classrooms as mount Sinabung volcano spews thick volcanic ash in the background on February 10, 2017 in Karo, Indonesia. Mount Sinabung is one of the most active volcanoes in Indonesia and last erupted in May 2016, killing seven people. (Photo by Albert Damanik/Barcroft Images)

Joshua Patino stands on a ladder to put finishing touches on a giant dinosaur exhibit at PAX East in the Boston Convention and Expo Center, Thursday, April 21, 2016, in Boston. PAX East, an annual celebration of gaming culture, is expected to draw tens of thousands of visitors Friday through Sunday. It's a place where serious gamers can preview unreleased video games and devices, compete in tournaments, hear live music and meet others for whom gaming is a way of life. (Photo by Elise Amendola/AP Photo)

“A snapshot from mountaineer's life”. Have you ever wondered how does a mountaineer's day start? I will give you a hint: you wake up at 3 am, set the stove, wake up your partner, pretend it is warm, quickly consume a high-calorie breakfast, watch your friends slowly ascending the icy slopes of your dream summit with their tiny head torches glimmering against perfectly blue ice, and hope for the good weather. One would ask: why all this trouble? The answer is easy: for the love of the adventure and the unknown. Location: Chamonix, Haute Savoye, France. (Photo and caption by Kamil Tamiola/National Geographic Traveler Photo Contest)

ATTENTION! All pictures are presented in high resolution. To see Hi-Res images – just TWICE click on any picture. In other words, click small picture – opens the BIG picture. Click BIG picture – opens VERY BIG picture.

Two carnival revellers masquerade as Leonardo da Vinci's painting “Mona Lisa” pose in St. Mark's Square in Venice, Italy, Sunday, January 31, 2016. Carnival-goers in Venice are being asked by police to momentarily lift their masks as part of new anti-terrorism measures for the annual festivities. (Photo by Domenico Stinellis/AP Photo)

Flying pigeons pass over Nepalese street vendors near the earthquake damaged UNESCO World Heritage Site, Durbar Square in Kathmandu on May 20, 2015. Nearly 8,500 people have now been confirmed dead in the disaster, which destroyed more than half a million homes and left huge numbers of people without shelter with just weeks to go until the monsoon rains. (Photo by Ishara S. Kodikara/AFP Photo)

Artist Joe Hill poses on his 3D artwork, from the “Joe and Max” project as part of an advertising campaign, during its presentation at a park in Moscow, Russia, July 4, 2015. (Photo by Sergei Karpukhin/Reuters)

A woman poses next to two mailboxes along a street in Taipei on August 11, 2015 that were reportedly bent by strong winds brought by Typhoon Soudelor over the weekend. The two iron mailboxes have become an unlikely attraction, drawing thousands of snap-happy visitors and have even become a backdrop to a wedding photo shoot. The typhoon, which hit in the early hours of August 8 and was billed as the most powerful typhoon this year, uprooted trees, brought down electricity poles, knocking out power to a record 4.3 million households, while leaving eight dead and four missing. (Photo by Benjamin Yeh/AFP Photo)