I've mentioned a couple times lately that my family went on a road trip to South Dakota a couple weeks ago. The craft beer scene was absolutely awful (see South Dakota Six Pack ... Kinda Sorta Not Really), but we really did a bunch of fun things as a family.
My favorite part of the trip was visiting Badlands National Park. I could have spent several days exploring the geologic formations. It was really awe-inspiring.
The first "trail" area we came to was my favorite. I guess we started at "Door Trail" (see the Hiking page of the National Park website), but once the boardwalk ended, the boys and I just took off in the wide-open space. We explored the various gullies and canyons. Most National Parks want visitors to stay on official maintained trails. Here, we were encouraged to go wherever we wanted. I honestly could have spent all day just in this place (if I had enough water).
If you are ever in the area, I strongly suggest visiting Badlands National Park. Make sure you bring sturdy hiking shoes / boots and lots of water. Also, you'll want sunglasses.
These pictures don't come close to capturing the awesomeness of the park, but here they are none-the-less.