Millions of people in 183 countries celebrated the 30th anniversary of Earth Day on Saturday, with rallies, marches, demonstrations, car-free days, and fairs, many of them focused on the theme of clean energy and global warming. At the flagship Earth Day event in Washington, D.C., hundreds of thousands came out to hear speeches from politicians, listen to music from such artists as James Taylor and Third Eye Blind, and catch sight of Leonardo DiCaprio and other celebs. Big events also took place in other cities throughout the U.S. and the world, including Tel Aviv, Tokyo, London, Mexico City, Sydney, New Delhi, and Capetown.