Don't forget National Park Week, which extends through April 27. Pay no entrance fee if you visit this weekend. The National Park Foundation shares this infographic to encourage more people to participate in America's Best Idea--establishment of the national park system.
- Sequoias, the largest trees in the world, can be as tall as a 26-story building.
- There are more than 4,900 caves in our national parks.
- Black bears eat up to 20,000 calories a day.