Perth, Australia, During Earth Hour

Darkness descends on Perth, Australia, during Earth Hour 2008. In addition to cities, Earth Hour partners last year included famous monuments such as the Colosseum in Rome, Londons City Hall, New York City's Empire State Building, and the Golden Gate Bridge in San Francisco.

"Earth Hour will focus global attention on addressing the issue of climate change," Earth Hour executive director Andy Ridley said in a statement.

In 2009, "we are asking one billion people to take part in what is essentially the first global vote for action on climate change by turning off their lights for one hour and casting a vote for Earth."

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