You pay a fee to get into the Carrillo National Monument Park. I think it was like $10. But once you're past the gate then everything else is free. There is no additional fee to go into the lighthouse, or the visitor center or the tidepools.
Yes it does because it is a national park. Unfortunately, I cannot remember how much it costs because we had a pass. If you are U.S. military active personnel you can get a pass to the national parks for free.
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