Earth Hour is the single, largest, symbolic mass participation event in the world.
Born out of a hope that we people could be mobilized to take action on climate change, Earth Hour now inspires a global community of millions of people in 7,001 cities and towns across 152 countries and territories to switch lights off for an hour as a massive show of concern for the environment.
This year University of Debrecen joins Earth Hour, the floodlights will be turned off for an hour on 23 March.
http://www.youtube.com/watch?v=2UywrjnOaUE&feature=player_embedded