bobbytables

(emphasis mine)

It seldom makes sense to obtain foreign currency before traveling. Unless for some reason you don't have a card with favourable policies, just use an ATM once you're there. Cash foreign exchange rates are almost always inferior to just using an ATM. Often you're better off using an ATM than exchanging cash even if you pay a small fee to your bank. As long as there's no fixed portion to the fee, this also allows you to take small amounts out as you need them, rather than trying to guess how much you need before you leave.

Edited to add: remember not to let the ATM do the currency conversion for you though!