America has 412 national parks, monuments, historic sites, and preserves ranging from simple campgrounds to vast underground caverns to giant 1,000-year-old forests. All of them are under the stewardship of the National Park Service, which will turn 100 years old on August 25.

I can't say we visited every one on our many camping trips, day excursions and family reunions, but when I was a kid, the national parks were the place to go for summer fun. That's where I learned to fish, hike, pitch a tent, make a campfire and cook outdoors. And on college road trips, that's where we'd  always park the VW Bus for a day or two of rest.

During the Park Service's Centennial celebration, from August 25 through August 28, all 412 parks will be free to the public. They're also hosting events across multiple parks, like Sing Across America where you can hear local children's' and youth choirs perform a song written especially for the centennial. Visit the Parks Service website to locate a park near you so you can celebrate some of America's most precious treasures and 100 years of National Parks Service stewardship.