There is a general parking section that is covered with your ticket.
Parking is almost never free there. This can be an add on to your ticket package but u most likely will have to shell out some cash for parking. Unless you have your friends meet you in town and transport you to thier camp.
I would double check with your camp mates and see if there's room for your car. Sometimes you need parking passes. (I don't normally camp at the Gorge's campground, but I've checked it out tons of times.
You park in the camping area and set up behind your car
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