Originally Posted by
pinniped
Depending on the city/country, you may not need any physical banknotes at all.
But if you do, the ATM in Europe is the way to go. If you are in a touristy area, just watch out for dynamic currency conversion (that is, the ATM offering to charge you in your home currency). Always decline that.
Ditto, I was down under and never got any local currency. I used my AmEx or Visa the whole time. That said, I am in Europe/UK/Switzerland often enough so usually have a stash local currency. If I need some immediately I grab some at the airport ATM. Worst case I carry a couple hundred in US bills.
And to reiterate - never use the dynamic currency conversion - always pay in the local currency.