National Park Week starts this weekend, a good time to plan a trip to Yosemite or Joshua Tree and take advantage of free admission on Saturday and Sunday.
It's part of an effort to honor "America's best idea" and get more Americans to go visit, particularly as the National Park Service revs up for its centennial in 2016.
From the video, here's how Gordon-Levitt explains why national parks were created:
"In the early 20th century, huge, rich, powerful men and corporations were snapping up enormous parts of the country and exploiting ... them, not necessarily treating them well, just trying to make money with them. The idea that 100 years ago our government stepped in and said, 'Hey, we're protecting these plots of land and preserving them as national treasures' and now 100 years later it's still happening...."
For more trip-planning information, the foundation offers free a guide you may download, such as "Happy Trails: 25 Unforgettable National Park Hikes" and "Parks for Play: 35 National Park Adventures for Kids of All Ages."
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