My Great Grandfather was a tough old bird and back in the Teens, 1920's and 1930's he would think nothing about piling Great Grandma in the car (Model-T iirc) and throwing in an old army surplus tent and some army surplus (WWI btw) sleeping bags, some wood and axe and cans of beans and head off across the country, all over parts unknown. Yes, he had one of those radiator water bags on the front (I still have it in my garage somewhere!)
As for my growing up, I'm not a geezer but I do remember piling into out 1965 Volkswagen built in bus. Mom and Dad would sleep on the couch foldout double bed, my oldest sister on the floor beneath the bed and me and my other sister in the front seat with me in a hammock hanging over the front seat! Damn it if she didn't always find some pine needles to stick up into my rear. Until I'd cry myself to sleep! LOL
I don't remember how we did it but we did. Family of 5 in a VW camper w/ gear and clothes and food. My Dad blew 2 engines in the year we owned the VW. I remember driving (helping my Dad drive) going over the Going To The Sun Highway. Also breaking down in Bozeman, MT and my Dad cussing in quite a prolific way that he was going to "get rid of that so and so VW" me taking him seriously and having to have my oldest sister calm me down and that Dad didn't really mean it!

By the next year or two, my folks bought a tent for my sisters and I moved downstairs into the lovely front seat!
Good memories!
WoodGlue