It's become a common sight at Shenandoah National Park in Virginia: People drive up to the entrance station, buy a pass and then turn around and leave, not bothering to even enter the park. "I've been ...

Fun fact: There are 417 national parks in the U.S., spanning across more than 84 million acres. And if you're 62 or older, $10 will get you into all of them for the rest of your life. It's not just ...