Depends on the site you reserve and how many nights... Around 23.00 a night, I think... But go to the State Park Reservation site and find out if there are sites available and what cost...
Check the website for this park and it will give you all of the info you need . One of the best spots to camp in Washington !!!
I don't know, we visited last week in a sailboat with a state park sticker. You might want to check their website
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