The ones behind the Iron Curtain would have to have been very elite!!!!! I rode in a bus through East Germany to Berlin in the early 80’s....scary. I do not see it.
I was in Budapest in 1972 (also behind the Iron Cutain). It wasn’t scary, as long as you stayed with the group (college).
If they were truly elite, they could have been at a boarding school in Switzerland, maybe the one that Princess Diana went to or similar. I remember reading that it was very exclusive.