All great advice so here is mine. That time of year be sure to make reservations in advance. Nothing like pulling into a campground and they say no sir, you don't have a reservation. Grrr. Had it happen twice along 101. Seems one reservation made would have put me in Mt. Rushmore. That would have been quite a drive in one day.
If possible, talk directly to the campground and make sure it is the campground and not a booking service.
Myron & Deborah
08 HR Endeavor 40 SKQ
2012 Ford Edge Limited FWD 3.5L
Aluminator tow bar, Demco base plate