![Earth Day [112:365]](http://farm3.static.flickr.com/2127/4545549593_b3be59fbe3.jpg)
Photo credit: Michael Daines
Brookside Nature Center is sponsoring a hike on the Billy Goat A Trail near Great Falls in the morning, and a tree walk at the nature center on Friday afternoon.
And the US Botanic Garden is hosting an Earth Day Celebration Friday from 10:00 to 2:00 at their space on the Mall.
You can search the Earth Day Network for more events...and as always, there's lots more on our calendar for the weekend!