1 of 9
A view of the Supertree Grove structures at Gardens by the Bay before and after lights are switched off to mark Earth Hour, in Singapore. | Earth Hour, which WWF organises, encourages people worldwide to turn their lights off for 60 minutes to raise awareness about environmental issues.
Image Credit: Reuters
2 of 9
The Sydney Opera House before and during Earth Hour, in Circular Quay, Sydney, Australia. | Participants turn off lights in residential buildings as well as the illumination of famous city landmarks and monuments for one hour between 8:30 and 9:30 p.m. local time.
Image Credit: Reuters
3 of 9
The Sydney Harbour Bridge | Earth Hour is an annual international event, which has been held since 2007 on the last Saturday in March by the World Wide Fund for Nature.
Image Credit: AFP
4 of 9
Namsan Seoul Tower illuminated before (L) and after (R) the lights were turned off to mark the Earth Hour environmental campaign in Seoul, South Korea.
Image Credit: AFP
5 of 9
Seoul City Hall illuminated before (top) and after (bottom) the lights were turned off to mark the Earth Hour environmental campaign in Seoul, South Korea.
Image Credit: AFP
6 of 9
Quezon Memorial Shrine before and after the lights were turned off to mark the Earth Hour environmental campaign in Quezon city, suburban Manila, Philippines.
Image Credit: AFP
7 of 9
A combination picture shows the Temple of Dawn before and during Earth Hour, in Bangkok, Thailand.
Image Credit: Reuters
8 of 9
A combination picture shows a view of the Hong Kong's Central financial district before and after lights are switched off to mark Earth Hour, in Hong Kong, China.
Image Credit: Reuters
9 of 9
Kuala Lumpur's skyline with Petronas Twin Tower at the centre, during and after observing Earth Hour, in Kuala Lumpur, Malaysia.
Image Credit: Reuters