We volunteered in a national park once and one of our duties was to assign the incoming reservations with a campsite that their RV would fit. We found there were very few on our chart we used that would be suitable for a big rig - big meaning 35+.
So we personally asked if we could create a new chart. We walked the campground with a tape measure and measured each site and then made a chart with what sites would accommodate what size rig plus a vehicle.
The rangers were amazed at how many of the sites could accommodate a 35-40' RV. I will say that any size RV could drive the road in the campground - no obstacles.
Bottom line.... not many campgrounds really do measure their sites. It's all an estimated guess.
