This is a great getaway spot--quiet, not too crowded, and with the Robert Ferguson Observatory just up the road (time it right and you can get in on some of their events, which are very cool).  The campsites on the spur back up into shade, a welcome relief in the summertime.  "Glamping" sites available with reservations.  No cell service but high-speed internet is available for a fee at the Visitor Center.  A great place to camp if you're looking for a laid-back outdoor experience in the wine country.  (And dogs are allowed, always a plus for those of us with K9s.)