So, what did you do for Earth Hour 2011? We hope shutting off your lights between 8:30pm and 9:30pm were part of it!

Sydney, Australia was home to the first Earth Hour in 2007. On that day, 2.2 million homes and businesses across the city turned out their lights for one hour – a stand against climate change. A year later, Earth Hour went global. And we want to know – how did you take part?