Sydney Opera House in the dark over Earth Hour

[March 31, 2012]  SYDNEY (AP) -- Sydney's iconic Harbor Bridge and Opera House has gone dark as Australians switched off lights around the country for an hour Saturday as part of a global effort to shine a spotlight on climate change.

Hundreds of landmarks around the world including Washington's National Cathedral, London's Clock Tower, the Great Wall of China and Tokyo Tower will be dimmed at 8:30 p.m. local time.

The central Sydney icons have been taking part in the annual event since Earth Hour began as a Sydney-only event in 2007. Australia is among the first countries to hit the light switches each year.

[Associated Press]

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