A devotee offers prayers to the setting sun during the "Chhat" festival at Bagmati river in Kathmandu, Nepal November 17, 2015. Hindus in Nepal celebrate "Chhat", a four-day festival that honours the sun god, by praying at sunrise and sunset, and seek blessings for one's family by giving offerings. (Photo by Navesh Chitrakar/Reuters)

A face of a devotee covered with her cloth is pictured as she offers prayers to the rising sun during the "Chhat" festival in Kathmandu, Nepal November 18, 2015. Hindus in Nepal celebrate "Chhat", a four-day festival that honours the sun god by praying at sunrise and sunset and seeking blessings for ones family by giving offerings. (Photo by Navesh Chitrakar/Reuters)

Buzludzha is a historical peak in the Central Stara Planina, Bulgaria and is 1441 metres high. In 1868 it was the place of the final battle between Bulgarian rebels led by Hadji Dimitar and Stefan Karadzha and the Ottoman Empire. The Buzludzha Monument on the peak was built by the Bulgarian communist regime to commemorate the events in 1891 when the socialists led by Dimitar Blagoev assembled secretly in the area to form an organised socialist movement with the founding of the Bulgarian Social Democratic Party, a fore-runner of the Bulgarian Communist Party. The Monument was opened in 1981. No longer maintained by the Bulgarian government, it has fallen into disuse. Buzludzha is reached by a 12 km side road from the Shipka Pass.

Some of the worlds most iconic cities have been photographed as youve never seen them before in the shape of tiny round planets. By using a pioneering method of aerial photography, each location can be now seen at a full 360 degree angle. After some skilful manipulation on Photoshop known technically as stereographic projection, each sweeping panorama is then turned into a small circular shaped image. Whether its the Eiffel Tower, The Empire State Building or the Shanghai Skyline, each image manages to show hundreds of miles of city landscape. Here: the French Riveria of Cannes, France. (Photo by Airpano/Caters News)

The Kingdom of Pagan (also commonly known as the Pagan Dynasty and the Pagan Empire) was the first kingdom to unify the regions that would later constitute modern-day Burma (Myanmar). Pagan's 250-year rule over the Irrawaddy valley and its periphery laid the foundation for the ascent of Burmese language and culture, the spread of Burman ethnicity in Upper Burma, and the growth of Theravada Buddhism in Burma and in mainland Southeast Asia.

Children displaced as a result of Boko Haram attacks in the northeast region of Nigeria, run at a camp for internally displaced persons (IDP) in Yola, Adamawa State January 13, 2015. Boko Haram says it is building an Islamic state that will revive the glory days of northern Nigeria's medieval Muslim empires, but for those in its territory life is a litany of killings, kidnappings, hunger and economic collapse. (Photo by Afolabi Sotunde/Reuters)

Joaldunaks return in a trailer to their town at the end of Carnival between of the Pyrenees villages of Ituren and Zubieta, northern Spain, Monday, February 1, 2016. In one of the most ancient carnivals in Europe, dating from before the Roman empire, companies of Joaldunak (cowbells) made up of residents of two towns, Ituren and Zubieta, parade the streets costumed in sandals, lace petticoats, sheepskins around the waist and shoulders, coloured neckerchiefs, conical caps with ribbons and a hyssop of horsehair in their right hands and cowbells hung across their lower back. (Photo by Alvaro Barrientos/AP Photo)

The Tribute in Light is seen behind the Empire State Building on September 10, 2011 in New York City. The Tribute in Light is an art installation honoring those who perished in the 9/11 attacks. New York City and the nation are preparing for the tenth anniversary of the terrorist attacks on lower Manhattan which resulted in the deaths of 2,753 people at the World Trade Center. (Photo by Mario Tama/Getty Images)