At wat time they open

They are open 24/7 but you will have to walk until the shuttles start running at 6:30 am. You can enter a park before they open they just expect the honor system and that you pay them the next day(or same day.) I did that at the north rim of the Grand Canyon national park to watch sunrise this am.

They technically open at 6 a.m.

A must see park

Theyre open 24/7 but the shuttles run from 0630am-930pm