Earth Hour Around the World 2011

This picture shows the Welcome Statue fountain in Jakarta, Indonesia before and during the switch off (Supri/REUTERS)

Paris: These photos show the Eiffel Tower moments before it submerged into darkness and once the lights were turned off. The symbolic energy-saving exercise which happened across the globe (Martin Stenning/Rex Features)

Black out: The lights around Sydney's Harbour and the iconic Opera House are recognised across the world. The top image shows how the area would normally look at night and below, in darkness to celebrate 'Earth Hour'. (Drina Thurston/AFP/Getty Images)

The Acropolis and the Herodion in Athens also switched off to show support for Earth Hour. (John Kolesidis/REUTERS)

China also took part and this picture shows the 'Birds Nest' National Stadium and the National Aquatics Centre. This year, 85 Chinese cities pledged to turn their lights off - more than double from last year (David Gray/REUTERS)

This image shows the 'Birds Nest' stadium in Beijing, China during the power switch off which will see iconic landmarks switch their lights off in a bid to try and create a more sustainable world (ChinaFotoPress/Getty Images)