Earth Hour

http://www.earthhour.org/

Acropolis Earth Hour 2010

Hundreds of millions of people, businesses and governments around the world unite each year to support the largest environmental event in history – Earth Hour.  

More than 5,200 cities and towns in 135 countries worldwide switched off their lights for Earth Hour 2011 alone, sending a powerful message for action on climate change. It also ushered in a new era with members going Beyond the Hour to commit to lasting action for the planet. Without a doubt, it’s shown how great things can be achieved when people come together for a common cause.