This Audrey Hepburn photo contains
sombrero, boater, leghorn, panama, panama hat, sailor, skimmer, straw hat, fedora, felt hat, homburg, stetson, and trilby.
There might also be
beaver, castor, porkpie, porkpie hat, dress hat, high hat, opera hat, silk hat, stovepipe, top hat, topper, and beaver.