Earth Hour takes place 8.30-9.30pm local time on Saturday 28 March. WWF organise the event and the idea is that as many people as possible across the globe turn off their lights for one hour. It's only been going for two years and the numbers have gone from 2.2 million in Sydney to 50 million last year. this year they're aiming for the big one billion. At last count 1,760 cities in 80 countries had signed up to take part. In the UK 155 prominent landmarks or buildings will be plunged into darkness for the allotted 60 minutes. If you're anywhere near the London Eye, Tyne and Gateshead Bridges, Brighton Pier, MEN Arena in Manchester, Edinburgh Castle or the Millennium Stadium in Cardiff, watch out for their lights going out.
For more info check out earthhour.wwf.org.uk. Join in, switch off.
