The Earth Hour campaign was started in 2007 by a nonprofit organisation 'World Wildlife' (WWF) with a message "a lot can be achieved if the world unites to reverse climate change."
On March 19, millions of businesses and individuals worldwide observed 10th edition of the camapign from 8:30 - 9:30 PM local time.
Here are the pics from around the globe:
Individuals were encouraged to participate and adjust lifestyles to trim their carbon footprints.
The event was packed to accommodate involvement of communities to the environment.
Yesterday World Wildlife Fund hosted its first ever Earth Hour event here.
Around 300 buildings in central Moscow, shut off their lights as part of the campaign.
Lights were switched off across famous Victoria Harbour skyline.
People from different walks of life turned up to celebrate Earth Hour here.