In 2007 Sydney started the first ever Earth Hour event, by persuading as many businesses and individuals as possible to switch off their lights.
This year the city was almost completely engulfed in darkness; over two million individuals and more than two thousand businesses took part.
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Masked gunmen reportedly opened fire on the bus full of Coptic Christians as it travelled towards a remote monastery outside of Cairo.
The parents of the girl - dubbed Miracle Matilda by doctors - have thanked the medical team for refusing to giver up on her.
Barack Obama has delighted the crowds at St Andrew's golf course as he teed off his visit to Scotland with a game of golf.