Enjoy free admission to nearly 400 national parks, and more than 1,400 museums and cultural institutions across the United States on Saturday, Sept. 29, 2012, to celebrate, respectively, the 8th Annual Museum Day Live! and 19th Annual National Public Lands Day.
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To visit a museum, go to this Smithsonian website to find a participating location near you. (After filling out a form, you'll get instructions on how to print out a ticket good for up to two people per household.) Participating venues include New York's Museum of Arts and Design and the Museum of Contemporary Art in Chicago.
If you're interested in visiting a national park, checkout the National Park Service website. If you want to spend part of National Public Lands Day volunteering on a tree-planting or park cleanup project, you can find more information at the National Public Lands Day website.