I've traveled in Europe for round about 30 years (yikes I am old....). Got an AMEX card before my first trip. Used it in all major cities at everything from bookstores to grocery stores (the big chains like Hertie and Karstadt). Ran out of cash and got an advance at a local office by reciting my bank account info - bet you can't do that anymore...but you can cash a check if you bring a blank one along. My daughter is now in Peru where she uses AMEX's pre-paid card to withdraw her father's cash ($ or local stuff) from any ATM with the AMEX sticker, and there are a lot of them. I also take another card on all trips, but the number of times I must use it are few. After some careful calculations from my last trip, I saved about 3% using the card rather than converting currency. And, no, I am not employed by them, and you can of course do all this with other cards too......