Chinese artist Kong Ning walks in her costume made of hundreds of orange plastic blowing horns during her art performance raising awareness of the hazardous smog in front of the Drum tower in a historical part of Beijing on a very polluted day December 7, 2015. Kong, whose works include themes related to China's air pollution problem, named her new performance “The Orange Horns Bride Marries the Blue Sky” and presented it dressed in orange, the colour of the second highest pollution alert level issued again in Beijing as hazardous smog blankets the capital. (Photo by Damir Sagolj/Reuters)

A woman walks through flood water during heavy downpour at a street in Genoa, Italy, 10 October 2014. At least one person died due to flooding after heavy rains caused the Bisagno river, which runs through Genoa city to overflow. Part of the city was in black-out with flooded streets and parked cars dragged away by the water's force. (Photo by Luca Zennaro/EPA)

People walk under stands with balloons placed along the former Berlin Wall location at Mauerpark, which will be used in the installation “Lichtgrenze” (Border of Light) in Berlin November 7, 2014. A part of the inner city of Berlin will be temporarily divided from November 7 to 9, with a light installation featuring 8000 luminous white balloons to commemorate the 25th anniversary of the fall of the Berlin Wall. (Photo by Pawel Kopczynski/Reuters)

Sunrise over a moor viewed from Littaford Tor, Dartmoor, UK, 2016. Autumn visits the windswept moors and granite tors of Dartmoor earlier than the rest of the south-west. While there aren’t many trees here, autumn shades appear in golden ferns and tan heather. Littaford Tors, near Two Bridges and a mile from Princetown, is a short walk and can be combined with a visit to the adjacent Wistman’s Wood. (Photo by Stuart Holmes)

An Indian Air Force person walks carrying a Nepalese child, wounded in Saturday's earthquake, to a waiting ambulance as the mother rushes to join after they were evacuated from a remote area at the airport in Kathmandu, Nepal, Monday, April 27, 2015. The death toll from Nepal's earthquake is expected to rise depended largely on the condition of vulnerable mountain villages that rescue workers were still struggling to reach two days after the disaster. (Photo by Altaf Qadri/AP Photo)

Sheep walk as they are herded to summer pastures in Serra da Estrela, near Seia, Portugal June 27, 2015. In late June, shepherds young and old in the Seia region of central Portugal start guiding sheep, goats and cattle to the Serra da Estrela, the country’s highest mountains, in search of better pastures. There they stay until the end of September. Modern-day shepherds may have mobile phones to keep in touch with family and friends, but their lifestyle has changed little for centuries. The sound of cowbells and the bark of longhaired mastiffs starts early in the morning as the animals – often decorated with traditional woollen balls on their horns – are herded up steep, narrow paths. (Photo by Rafael Marchante/Reuters)

A man walks with a giant rake during carnival celebrations in Zubieta January 27, 2015. Bell carrying dancers known as Joaldunak from Zubieta and neighbouring Ituren visit each other's villages performing a ritual dance to ward off evil spirits and awaken the coming spring. Alongside the dancers, villagers dress in bizarre and frightening costumes to harass and scare visitors. (Photo by Vincent West/Reuters)

Indigenous woven backpacks called guayare are seen in front of a house in Paraitepui village, before a walking excursion to Mount Roraima, near Venezuela's border with Brazil January 13, 2015. A mysterious table-topped mountain on the Venezuela-Brazil border that perplexed 19th century explorers and inspired “The Lost World” novel is attracting ever more modern-day adventurers. (Photo by Carlos Garcia Rawlins/Reuters)