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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A cloudy start in the east with the odd spot of drizzle, but brightening up here through the morning.
Charlie Gard's parents are spending their "last precious moments" with the terminally ill boy after a legal fight over his treatment ended.
Leaseholds on new-build houses could be banned outright under proposals to stamp out abuses of the system.