Photo: Earth Day, 1970

137 of 415
April 22 1970 New York City

credit: Frank Castoral

137 of 415

The first Earth Day was held on April 22, 1970. It was a sunny day in New York City, and thousands of New Yorkers marched down 5th Avenue, from Midtown to 14th street. Today, over 1 billion people observe Earth Day around the world, according to The Earth Day Network.

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