You usually don't need a pass unless you park (just don't walk away from your vehicle) or if a ranger stops you (mostly on the weekends).
Bill's Place (liquor store) located just past Sand Cyn & Sierra Hwy sell the Adventure Pass! He has a sign outside!!
How much for the pass?
They have a ranger station on site. If no one is there, just park. They will put what looks like a ticket on your windshield and you can pay by mail. You can usually also buy a day pass at the local convenience stores.
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