I recall traveling with my family in the late 1950's and during the 1960's.
We lived on one end of the US, Mom's family was the other end, so lots of road trip vacations.
It was quite an adventure, but frustrating to drive in that the Interstate system was in such an infant state there were just so many unfinished areas.
Driving down a good four lane Interstate and boom, back on two lane for a while. Then just as suddenly back on another finished part of the Interstate.
Back and forth. Oh well, still good memories. Gave me the travel bug I have now.