On Saturday March 27th, 2010, millions of people from around the world turned off their lights as part of the World Wildlife Fund’s global Earth Hour campaign.

In Canada, homes and businesses, along with national monuments such as the CN Tower in Toronto, the Lion’s Gate Bridge in Vancouver and the Niagara Falls plunged into darkness.

According to CBC, demand for electricity fell across the country, dipping by as much as 4 percent in Ontario, and, according to another article, by 1.04 percent in B.C.

Andy Ridley of the World Wildlife Fund told the CBC that he hoped this year’s Earth Hour will lead to a stronger climate deal than what world leaders managed to create at the Copenhagen summit last year.

The WWF started Earth Hour in Australia in 2007. By 2008, the initiative had become a global campaign against climate change.

Check out the WWF's flickr gallery for some great before and after shots of how Earth Hour 2010 went down across the country.