Rescued Dutch hikers exit a search and rescue snowcat after they were brought safely to Grotli, Norway, February 26, 2016. Thirteen Dutchmen who were stranded while hiking in central Norway's mountains were found after snowmobile patrols by the Red Cross. Snowcats from the Red Cross are now moving ahead to pick the hikers up. (Photo by Torstein Boe/Reuters/NTB Scanpix)

On August 18, 2012 the infection spreads again as the undead hordes shamble through Vancouver in search of brains. The annual Zombie Walk has been going on for years and each year gets bigger and bigger. (Photo by Gord Gallagher)

Ace Wu searches the deep to photograph stunning underwater creatures. Against their predominantly black backdrops, Wu’s breathtaking subjects glow with sublime vibrancy. In one, a fearsome fish glares at the camera with rows of sharp teeth showing, while in another, a translucent octopus looks like an extraterrestrial. Here: Wunderpus larva. (Photo by Ace Wu/Caters News Agency)

People take a selfie at the abandoned former Soviet R12 nuclear missile launch site in Zeltini, Latvia, July 22, 2016. Hidden in the forests of Aluksne, near Latvia's north-eastern border with Russia, the remains of a former Soviet nuclear missile base are a magnet for tourists now rather than a top-secret site manned by soldiers. (Photo by Ints Kalnins/Reuters)

A muslim pilgrim walks through the site where dead bodies are gathered in Mina, Saudi Arabia during the annual hajj pilgrimage on Thursday, September 24, 2015. Hundreds were killed and injured, Saudi authorities said. The crush happened in Mina, a large valley about five kilometers (three miles) from the holy city of Mecca that has been the site of hajj stampedes in years past. (Photo by AP Photo)

Fort Bourtange is a star fort located in the village of Bourtange, Groningen, Netherlands. It was built in 1593 under the orders of William the Silent. Its original purpose was to control the only road between Germany and the city of Groningen, which was controlled by the Spaniards during the time of the Eighty Years' War.

A member of the Eton public school O.T.C. (Officers Training Corps) practising shouting out orders during a training session, 20th January 1940. (Photo by Hulton Archive/Getty Images)

In Omdurman, the largest city in Sudan, the Qadiriyya Sufi order meets every Friday outside Sheikh Hamed Al Nil mosque, which houses the tomb of their 19th century Sufi leader. (Photo by Ala Kheir, John Burns and Ibrahim Algrefwi/Brownbook)