This time last year, this program was the impetus we needed to fulfill a goal I had to show my children our beautiful country. So we took full advantage last May/June and my family did an AMAZING 3 week trip in a rented Cruise America RV to swing a loop through the western states and hit as many parks as we could along the way. The NPs we visited included Zion, Bryce, Teton, Yellowstone, Badlands, Wind Cave, Great Sand Dunes, Mesa Verde, and the Grand Canyon as well as many National Monuments, National Forest, State Parks, and historic sites along the way. We had never even done an RV trip before but with 8 months of advance planning and reserving campground sites in the parks themselves wherever possible (booked 6 months in advance to the minute the reservation system opened up for our dates) it went very smoothly, and we had an incredible experience. It was our first real vacation in our 20 year marriage, and while we had a very ambitious itinerary our kids were old enough (10, 13, and 15) and fit enough to cover so much ground (literally, we did a ton of hiking and biking) and help out in the RV and at the campgrounds. At each National Park we had to show our pass (the paper voucher was exchanged for a plastic pass card they put in a hang tag for us – we took care of that in advance at Steamtown NP in PA) and also the rangers checked that our 4th grader was in the RV with us (she just came up front and waved to them each time). Several rangers joked that we owed her an ice cream each time we entered the park for how much money she was saving us 🙂 As someone else mentioned, we were pleasantly surprised that at Wind Cave the pass covered the cave tour fee (unlike for example Mesa Verde where the tour fees required to visit certain sites were not covered and had to be paid separately).