http://www.history.com/topics/holidays/earth-day largest civic, secular event in the world History Channel History.com See original article… http://www.history.com/topics/holidays/earth-day History: Earth Day videos and articles Earth Day expanded Earth Day http://www.history.com/topics/holidays/earth-day http://www.history.com/topics/holidays/earth-day http://www.history.com/topics/holidays/earth-day Earth Day The first Earth Day History.com, http://www.history.com/topics/holidays/earth-day History of Earth Day Earth Day Earth Day in 1970 History History Channel History.com http://www.history.com/topics/holidays/earth-day History.com Earth Day History Channel Earth Day feature History Channel The History Channel http://www.history.com/topics/holidays/earth-day Earth Day History http://www.history.com/topics/holidays/earth-day See original article… EARTH DAY – history.com History Channel http://www.history.com/topics/holidays/earth-day History.com the movement was hijacked by a politician History of Earth Day http://www.history.com/topics/holidays/earth-day http://www.history.com/topics/holidays/earth-day Earth Day Earth Day Earth Day in 1970 Earth Day feature EARTH DAY http://www.history.com/topics/holidays/earth-day *History - Earth Day “national teach-in on the environment.” global celebration Earth Day http://www.history.com/topics/holidays/earth-day History.com History.com, The first Earth Day History.com History http://www.history.com/topics/holidays/earth-day History Channel History in 1970 http://www.history.com/topics/holidays/earth-day Earth Day - HISTORY.com Earth Day History Channel http://www.history.com/topics/holidays/earth-day History Channel See original article… History Channel the movement was hijacked by a politician