Cities across the world switched off their lights to mark this year's 'Earth Hour' movement on Saturday.
Big Ben, the Houses of Parliament and UK landmarks went dark for an hour tonight as the UK took part in Earth Hour.
London prepares for Earth Hour
One Times Square switched off its iconic lights, to mark Earth Hour this evening. Landmarks across the globe turned off their lights at 8.30pm local time in a show of support for renewable energy.
New York's iconic Times Square has turned its lights out to mark Earth Hour, a global initiative raising awareness on climate change.
The lights have gone out in the Argentinian capital of Buenos Aires, as the last few countries mark Earth Hour today.
The United Nations headquarters in New York has switched off its lights as the city went dark for Earth Hour. The UN took part in the initiative alongside the WWF.
The lights have gone out at Senedd, Cardiff Bay for Earth Hour as part of a global effort to raise awareness about climate change.
Sophie Ellis-Bextor has performed in an LED light dress for Earth Hour.
Big Ben and the Houses of Parliament have gone dark for Earth Hour.