Having never done it, it amazes me that people sod off around the world with a backpack, and don't starve or die of exposure.
Do they just find a cash point every now and again nowadays?
Most debit and credit cards work around the world now. There is often an exchange service fee, but the actual exchange rate is competitive or even favorable. Of course, because the debit and credit cards work around the world, they work just as easily when the store has electronic payments options, so there's often no need to carry cash anymore. The store charges you, or the ATM dispenses in the local currency, and your bank does the rest, automatically. Sometimes the local limit may be a small amount compared to what you may be used to in UK. I mean small, sometimes as little as the equivalent of about £50, (reflecting the general cost of living in those areas) but multi-operations are sometimes possible, until you meet your usual limit for your card/account, for that day. Otherwise several withdrawals over subsequent days are necessary. You can workaround such limits by withdrawing over the counter. Although I've never explored the opportunity for cashback abroad, maybe because I've never used it in UK either, I suspect it's perfectly possible. I don't know if contactless works internationally. It does for locally issued cards.
It's even possible to take out and load up a specific debit card just for the purpose of use internationally. These can easily be topped up by a third party, such as a parent, etc as and when needed.
It's wise to inform your bank that you intend to use your card internationally, and in which countries.
Because few places accept travellers checks anymore it's usually necessary to cash them at a bank or larger type of organisation such as a hotel, but the exchange rate at places like hotels may not be favorable. But there are still a few specific reasons for using travellers checks, and if they're not used, you can return them unused.
So it's perfectly normal for people to sod off around the world with just a debit or credit card.
Failing any opportunity to buy anything or to use a card, the human kindness of foreign strangers will be overwhelming.
