Visitors to the Nightmare Fears Factory in Niagara Falls, Canada, are obliged to navigate their way round the supposedly haunted building in total darkness while live actors jump out of them. The Nightmare Fears Factory team have been using hidden cameras to take pictures of their guests' terrified reactions, which they've then posted on the company's Facebook page. And it turns out they're all pretty funny. (Photo by Nightmare Fears Factory)

Members of the Castellers “Vila de Gracia” start forming their famous human tower called “castell” in the Barcelona neighborhood of Gracia, Catalonia, Spain on Sunday May 19 2013. A “castell” is a human tower traditionally built during festivals in many places in Catalonia. At these festivals, several "colles" or teams compete to build the most impressive towers they can. (Photo by Emilio Morenatti/Associated Press)

In this photo taken April 15, 2015, Clay Hielscher of Overbrook, Kan., poses for a photo in his home made Iron Man suit. While he enjoys building the battlesuits of his favorite super hero, Hielscher said the real reason he is so passionate about his pastime is his 11-year-old daughter, Kyrianna. They design and construct the suits together. (Photo by Chris Neal/AP Photo/The Topeka Capital-Journal)

To an outsider, their passion is at times illegal and often on the verge of life and death. But climbing rooftops of high-rise buildings and exploring abandoned facilities is in the blood of these young Muscovites. The small group calls itself “Rudex”, which stands for “roof and decay exploration”, and is akin a Western youth craze known as urbex or “urban exploration” of man-made structures. Here: Urban explorer Vad Him of Rudex team jumps whilst on a rooftop in Moscow, Russia, August 14, 2017. (Photo by Maxim Shemetov/Reuters)

Taiwanese artist Hank Cheng poses with his miniature model of Taipei street scenes, in New Taipei City, Taiwan on June 17, 2018. While some of the vehicles used in Cheng's street scenes are bought in shops, all the buildings and small details like the magazines and the furniture for his model houses are created from scratch. (Photo by Tyrone Siu/Reuters)

A woman takes a photo on her mobile phone of a tiger during the media preview of Vivid Sydney at Taronga Zoo on May 19, 2019 in Sydney, Australia. An illuminated trail of almost 300 lit lanterns of endangered species will glow every night at the zoo during Vivid Sydney which runs from May 24 throughout Sydney with hundreds of lit buildings and exhibits which attract hundreds of thousands of visitors each year. (Photo by James D. Morgan/Getty Images)

A view of popular train street in the old quarter of Hanoi, Vietnam on July 30, 2022. Hanoi Train Street is one of the most well-known and exciting tourist destinations in the city and trains pass the street twice a day close to buildings on either side of the tracks. (Photo by Chris Humphrey/Anadolu Agency via AFP Photo)

Russian-born artist Vlad Korneev poses for a picture in his museum called “Designpanoptikum, Museum For Extraordinary Objects” on November 4, 2010 in Berlin, Germany. The museum displays objects whose outward appearance was determined by function rather than form, he says, and are the result of a collection he started while accumulating props for his photographic works. (Photo by Sean Gallup/Getty Images)