The first Earth Day was April 22,1970. Mother Nature did her part by providing a glorious warm spring day and thousands of Marylanders flocked outdoors to take a closer look at their environment and discuss its problems.

On that first Earth Day, thousands of new trees were planted, many bikes were ridden and much trash was picked up. An internal combustion engine was buried by students at the University of Baltimore and many lectures and exhibits were held throughout the state. The governor established the Maryland Council on the Environment.

This the 39th Earth Day. More people than ever are aware of the enviromental challenges we face, and if everybody does his or her part, hopefully we can find solutions.

Here are some photos looking back on past Earth Days.

This link goes to the EPA's history of Earth Day.

And here's the official Earth Day site.