Watch: Famous landmarks around the world power down for Earth Hour.

Famous landmarks around the world switched off their lights for an hour on Saturday night as part of an environmental awareness campaign, Earth Hour.

The Eiffel Tower in Paris, Rome’s Colosseum and the Parthenon in Athens were all used in the switch-off.

New Delhi’s Akshardham temple, the Sydney Opera House and the Sagrada Familia in Barcelona also joined in.

Earth Hour is organised by the World Wide Fund for Nature and it encourages people to turn off their lights for 60 minutes to raise awareness of environmental issues.