We were checked in an exceedingly pleasant ranger who offered lots of advice and even gave me a free matchbook. The sites were nice, and firewood is $8 for a gigantic bag full of about as much wood as a person can carry. The park itself is very pretty; you'll definitely want to make a drive or hike to see the eponymous Castle Crags. The campground is right near the highway, so you get a little bit of traffic noise, but nothing terrible.