The Canopy (left) in New Delhi being lit up in green on Saturday, the eve of World Environment Day. The event is observed annually on June 5. It is the United Nations' most important day for encouraging worldwide awareness and action for environment protection. Since it began in 1974, it has grown to become a global platform for public outreach that is widely celebrated in over 100 countries. This year's theme focuses on the illegal trade in wildlife under the slogan Go Wild For Life.