Millions across the world observed the Earth Hour by switching off electricity for an hour
New Delhi's India Gate as it is lit, at left, and then in darkness when the lights are turned out for one hour to mark Earth Hour.
A volunteer of the World Wide Fund For Nature (WWF) sets the final candles amongst about 5000 candles to picture the globe prior to 'Earth Hour' in front of the Brandenburg Gate in Berlin
A man launches a paper lantern during a ceremony to mark Earth Hour at Palace Square in St.Petersburg, Russia.
The Lions Gate Bridge is pictured with it's lights on, top, just before Earth Hour and bottom, after they were turned off for Earth Hour, in Vancouver, Canada
People set their 'Chinese lanterns' loose during Earth Hour from Hampstead Institute's Downtown Farm in Alabama, USA.
This two photo combination picture shows before, top, and after, bottom, the lights in buildings in the main business district are turned off during Earth Hour in Jakarta, Indonesia.
The lights illuminating the 9th century Hindu temple of Prambanan are turned off during Earth Hour in Yogyakarta, central Java, Indonesia.
The Pillar of Light monument illuminated at left and after its lights were switched off at right at the start of Earth Hour in Mexico City, Mexico.
People use candles to create the number 60, representing the minutes in an hour, to mark Earth Hour in La Paz, Bolivia.
