We visited the RV Museum located here in Elkhart, IN. It is a beautiful two story building designed to be a museum to display Recreational Vehicles.
The vehicles were very well presented. Also, keep in mind that in the very early days of RVing there were no campgrounds. These folks had to be hardy souls to venture out into the wilderness to dry camp. There were some "ice" boxes but no indoor plumbing until in the 30's.
One of the more modern RVs in the museum was a 1974 General Motors Motor Home. I did not include it in the photos. I still see these rigs on the highway and we have one here in our campground. These rigs were well designed and built and the proof is that some 38 years later these rigs are still rolling. The following link is the design story.