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When is Earth Hour 2024 and how can you get involved?
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UK landmarks switch lights off to mark Earth Hour
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UK landmarks to switch off lights for Earth Hour
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City skylines across the world plunge into darkness for Earth Hour
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Why is the world switching off its lights tomorrow for Earth Hour?
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Major global landmarks switch off the lights for Earth Hour 2018
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Inside the £26m bunker powering the City from down below
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Iconic London landmarks dim their lights to mark Earth Hour
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