Flying was always very expensive until the 60 s/70 s and out of most peoples pockets, but thanks to Freddie Laker, we all got tye chance to visit the costa brava etc. Before then most of us went by car, if you had one, or train or coach or both.
We travelled all over europe by train, the ferry over to France was a holiday in itself, through to Paris, change to the night isleeper (couchettes) lots to see and there was nothing better than waking at dawn to see the sun lighting the top of the snowy mountains in Switzerland. We usually went further south to Italy.
My children were mid teen befire they first flew , much older than their peers, but we always enjoyed the train. Still do, but havnt been abroad by train for many years. Havnt been abroad either cone to that. Fingers crossed maybe later this year.