I also travelled around the world in 89/90 and was using...

I also travelled around the world in 89/90 and was using American express travellers cheques in $100 US denominations.

At that time these were as good as cash but needed to be signed for with matching ID and could be replaced if lost or stolen.
That was the way to travel back then.
I met others on my travels that would be carrying 2 or 3 family credit cards and getting cash advances on them whenever needed.

Those were the days....