Saudis light candles to mark Earth Hour at the Ritz Carlton in Riyadh
Saudis light candles to mark Earth Hour at the Ritz Carlton in RiyadhReuters

Earth Hour 2013 was observed worldwide on Saturday (23 March) to show support for the planet and to raise awareness about conservation of energy. [Click on slideshow or click here to look at the pictures]

Millions of people from more than 150 countries and territories took part in the lights-off initiative and switched off their lights on Saturday night at 8:30 pm - 9:30 pm, in a bid to campaign against climate change.

Lights were turned off at important landmarks across the globe including Empire State Building in the US, Eiffel Tower in Paris, Elizabeth Tower (which houses the Big Ben) in London, Thames River, Burj Khalifa in Dubai, Turtle Tower in Hanoi, the imperial Schoenbrunn Palace in Vienna, Hong Kong's iconic skyline, Table Mountain in Cape Town and Times Square in New York.

For the first time, lights at Russia's Kremlin, the residence of the president, and Red Square were switched off to mark Earth Hour. Russia not only joined in the symbolic show of support for Earth Hour by turning off the lights, but its citizens also showed the world how they can create a positive impact. The World Wide Fund-Russia successfully secured signatures from more than 100,000 Russian citizens for a petition to make amendments in the current forest legislation.

The event of Earth Hour, organized by WWF for Nature, first originated in Australia to raise awareness about carbon pollution. Unlike previous years, Sydney kicked off the Earth Hour event this year by illuminatiing the Sydney Opera House in a deep green colour to symbolise renewable energy.

Asia Pacific countries including Japan, China, Singapore and India took part in the Earth Hour event. In Japan, the landmark Tokyo Tower, Hiroshima Peace Memorial (a UNESCO World Heritage Site) also plunged into darkness. In China, lights were dimmed at the former Olympic stadium "Bird's Nest" for one hour on Saturday.

India Marks Earth Hour

In India, important monuments including India Gate, Qutab Minar and Humayun's Tomb along with government buildings switched off their lights. The nation's capital joined other cities across the country to celebrate Earth Hour.

"The world is facing some of its most critical environmental challenges today and we all need to contribute as individuals. Every single responsible action to preserve the environment will add up to making a difference collectively," said Chief Minister Sheila Dikshit while taking part in an Earth Hour event.

Several markets, residential areas and hotels also opted to take part in the event and showed their commitment in preserving the environment by turning off lights.

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