Now this could help planning too! We may do Glacier NP next summer
In no order but close
1. Yosemite NP this you have to see on the trails, even the short trails
2. Yellowstone NP animals galore
3. Grand Tetons NP see above
4. Grand Canyon NP Its more than a big ditch
5. Lake Ouachita SP Arkanasas, (had to have one state park)
6. Any park where the sun shines, its warm and the stars shine bright in Texas