At 8:30 p.m. this Saturday the Sydney Opera House will go dark. Soon after, the Great Wall of China, the Burj Khalifa, the Eiffel Tower, Christ the Redeemer, the Empire State Building and countless others will follow suit. But if you notice any partial blackouts this weekend, fear not. The symbolic gesture simply marks each nation’s commitment to sustainability in 2013 in honor of Earth Hour.
Organizers of the annual event expect more than 7,000 cities and towns across 152 countries and territories on all seven continents to participate this year, including newcomers like Tunisia, Palestine, Galapagos, Suriname, French Guyana, Rwanda and the most remote island in the world: St. Helena.
Indeed, the Earth Hour movement has grown into the world’s largest voluntary action for the environment in the seven years since its humble inception in Sydney. From 2.2 million participants in 2007 to an event that reached an estimated 1.8 billion people in 2012, the organization has come a long way.
Earth Hour executive director and co-founder Andy Ridley partnered with the World Wildlife Foundation from the start and secured a major sponsor in the first year: PricewaterhouseCoopers.
“We wanted a conservative, if you will, and credible company to back our idea,” Ridley told IBTimes in a profile last year. From there, the movement began to spiral exponentially. By 2008, 279 cities and towns in 35 countries participated. The next year it was 4,000 cities and towns in 88 countries.