In New Delhi, the lights were switched off at the city's great arch. But in countries around the world, at 8:30 p.m. local time, people were switching off the lights Saturday for Earth Hour, a global call for international unity on the importance of climate change. Since beginning in Sydney in 2007, Earth Hour has spread to more than 180 countries, with tens of millions of people joining in, from turning off the porch lights to letting the Opera House go dark. But for an hour the arch stayed dark, a silent call for change. The candles spelled the Earth Hour motto of "60 ."

Source: ABC News March 24, 2018 19:30 UTC