Landmarks around the world will go dark for an hour tonight at 20:30 local time as part of the global environmental action Earth Hour.
The World Fund for Nature Protection is organizing this volunteer action for the 18th time, with the aim of warning about climate change.
The lights went out for the first time in 2007, on the Opera House in Sydney, Australia.
190 countries and territories are participating in the action, with great support on social networks.
