It's was $4 last time I visited
It was 8 dollars last summer
I think there was a parking charge in the past, there were signs, but it was free when I visited in January of 2020.
I do not know, you may try calling Merced county office, they should be able to help. I wouldn't think more than $10 at the absolute worst. I was there to perform a wedding and wasn't charged to get in and I don't think guests were either.
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