You can buy your pass in the store next to the restaurant el mexicano. Or you can pay only cash at the cabin were rangers are, right at the entrance. Only cash though. The area with gravel is free. Use your pass only if the area with gravel is full.
There is a Ranger's Booth it's about $6 - $7 also 1.5 -2 miles before the is a convenient store called Jessica's which sells them as well. Sometimes if you find parking on the gravel (dirt) area it's Free and can save your pass for next visit. Enjoy your visit, have fun, and especially, be safe.
There is a ranger booth at the entrance. It is $5 for the day. There is free parking in the back lot, it is a gravel lot.
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