A total of 350 landmarks in 178 countries took part in this year's event. In London, iconic venues including the London Eye, Buckingham Palace and Big Ben went dark. Further afield, landmarks including Brighton Pier, the Blackpool Tower and Edinburgh Castle also got involved.
On the South Bank, Londoners enjoyed dinner by candlelight at the OXO Tower restaurant, Skylon lounge and on City Cruises. Primo Bar on Westminster Bridge served a ‘Unplugged & Tonic cocktail’ to celebrate the event, with live acoustic music.
Other restaurants serving candlelit dinners included Bobo social and 86 Sustainable Restaurant Association-rated restaurants, such as River Cottage and The Shed.
The annual campaign sees participants around the world turn off non-essential lighting from 8.30-9.30pm to show they care about climate change.
Jennifer Clements, a spokeswoman for WWF UK said: "We have the knowledge and technology to reduce climate impacts and ease the pressures on the world's most vulnerable animals and people.
"Earth Hour reminds us that we have the power to make change happen. It’s a visible demonstration of the enormous level of support there is around the world for a united effort to tackle issues affecting our planet."
WWF opted for a panda stunt to drive awareness of last year's Earth Hour.
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