There is great differences between exchange rates at various points of conversion -- buyer beware. Often European airports have reasonable exchange rates and fees (but not always). Almost all US airports have terrible exchange rates (10% markup is typical, which is an outrageous charge). European street locations vary tremendously, usually a bank is better for any amount over $100 (they often charge a flat fee per transaction but give a better exchange rate). The "no fee" places are usually the most expensive and the worst deal.