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)

The Ring of Life is a 515-foot (approximately 157 meters) landmark built in the city of Fushun, China. The landmark is built with an observation deck accessible by elevator, as well as 12,000 LED lights. Having abandoned local entertainment projects due to the small local population, urban planners settled on building a sightseeing landmark instead in order to attract a tourist industry to the region. The structure uses approximately 3,000 tons of steel and cost an estimated $16M U.S. dollars.

A man takes a picture of part of what is set to be the UK's largest street art project on August 19, 2011 in Bristol, England. The See No Evil art project on Nelson Street in Bristol will see several multi story buildings in the street covered with art over the coming days. Organisers hope that the project, which has involved top graffiti artists from all over the world, will become a major tourist attraction for the west country city, often said to the spiritual home of Banksy. (Photo by Matt Cardy/Getty Images)

U.S. Park Police work to keep people away from the area surrounding the Washington Monument after a 5.8 magnitude earthquake struck the east coast August 23, 2011 in Washington, DC. Police officers said that unidentified material had fallen off the Washington Monument as a result of the earthquake. All the monuments and buildings along the National Mall have been evacuated and closed. (Photo by Chip Somodevilla/Getty Images)

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)

A detail of the Sagrada Familia Basilica, designed by architect Antoni Gaudi, in Barcelona, Spain, Wednesday, October 21, 2015. Barcelona's breathtaking La Sagrada Familia Basilica has begun its final phase of raising six immense towers. Presenting the project Thursday, chief architect Jordi Fauli said the central "Tower of Jesus Christ," the tallest of the six, will rise 172.5 meters (566 feet) high, making it "the tallest religious building in Europe". (Photo by Manu Fernandez/AP Photo)