Never travel to distant lands, with just one card. As before, a good (no foreign charges) credit card will cope far better than a cash card, except maybe when withdrawing cash from an ATM. For ATM’s and small day-to-day expenses, a cash card is fine.
I have two credit cards, one as a back-up to the other, each kept separately. The additional logic I apply is to have a credit limit high enough to get me home in a hurry in an emergency from just about anywhere in the world, backed by good quality travel insurance. Thankfully, I have never been called upon to use a card in a true emergency…. Touch wood, I never will.
My regular HSBC UK bank credit and debit cards I leave at home. I do though have a picture of both cards with me, meaning I could, if push really came to shove, use either or both for an online emergency purchase.