An armed man herds his cattle close to the village of Nimini in northern South Sudan, February 8, 2017. In the chaos of South Sudan's civil war, it took three years for Nyagonga Machul to find her lost children. Machul had traveled from her village to the capital when President Salva Kiir, an ethnic Dinka, fired his deputy Riek Machar, a Nuer, in 2013. (Photo by Siegfried Modola/Reuters)

Aerial photo taken on March 4, 2017 shows cole flower fields in Luoping County, southwest China's Yunnan Province. (Photo by Xinhua/Barcroft Images)

Zurab Gurielidze, a director of the Tbilisi Zoo, speaks to the media while standing next to a hippopotamus named Begi at the zoo in Tbilisi, Georgia, September 13, 2015. Tbilisi zoo, which was partly destroyed and some 300 animals escaped or died in the floods that also killed at least 19 people in June, was reopened on Sunday. (Photo by David Mdzinarishvili/Reuters)

Photographer Brian Finke spent nearly two years traversing the friendly skies, following the life of flight attendants in the air and on the ground, from Delta and Hawaiian Air, to Hooters Air, Southwest, Air France, British Airways, Air Asia, and dozens more. His images of flight attendants waving, applying makeup and deboarding plans while smiling appear as if they were ripped from an advertisement in a glossy magazine. Here: Tiger Airways, Singapore, 2006. (Photo by Brian Finke/The Washington Post)

A daredevil photographer is determined to capture London in a whole new light – by scaling the city’s many rooftops. Jacob Riglin, from Richmond Upon Thames, photographs the nation's capital from above – hanging from scaffolding, dangling his legs over the edge of buildings and looking down from perilous heights. Such images have gained the photographer, 20, an incredible fan base on Instagram, which has seen his follower count rise to more than 150,000. He said, “I had always been interested climbing and getting that adrenaline rush from feeling on top of the world”. Here: Jacob looking out to the London skyline. (Photo by Jacob Riglin/Caters News)

Urban photographer Roman Robroek spent five years scouring the continent for the grandest examples of forgotten architectural beauty. Here: Watch your step on this Polish spiral staircase. (Photo by Roman Robroek/South West News Service)

This photo of an elephant seal and Gentoo penguin shot by Andrew James in Yankee Harbour, Antarctica. (Photo by Andrew James/Travel Photographer of the Year)

Queen Ashi Jetsun Pema, 21, walks out after the marriage ceremony is completed on October 13, 2011 in Punakha, Bhutan. The Dzong is the same venue that hosted the King's historic coronation ceremony in 2008. The Oxford-educated king is popular in the country and the ceremony will be followed by celebration in the capital and countryside. (Photo by Paula Bronstein/Getty Images)