Camping should be free. I drove just outside the park, slept outside, and walked a mile eastward every day to get in.
These rocks are called hoodoos. They are formed partially by wind erosion, but primarily by water erosion. Due to the elevation of the park (8-9,000ft, 2,400-2,700m) it gets very cold during winter. Water freezes in the cracks, expanding, and perpetuating these bizarre formations.
I think this is when I peaked. All downhill from here for me.