April 22, 1970The first Earth Day is celebrated.
Earth Day is a day early each year on which events are held worldwide to increase awareness and appreciation of the Earth's natural environment. Earth Day is now coordinated globally by the Earth Day Network, and is celebrated in more than 175 countries every year. In 2009, the United Nations designated April 22 International Mother Earth Day. Earth Day is planned for April 22 in all years at least through 2015.