In peak season (here on a Wednesday) it is busy here and online reservations are really recommended.  This is a common campground set up (drive loop with sites patched along the way). The website was great for seeing reviews/ratings of specific sites. Booked 24 hrs in advance and got lucky with "prime" site, which was the last available site for my date. A little noisy with so many families in a full campground. But I would definitely return. Great mountain and dune hikes with trails easy to access from the campgrounds. Bear lockers, tent pads, picnic tables, fire rings at each site. Deer just feet from my site and mosquitos are there but manageable. 

NOTE: campsite fee does not include park entrance fee ($25/car)