The horses that will take to track at the Kentucky Derby on May 7 are supposed to be the stars of the show. And, sure, technically, they are.
But as always, they will have some competition for spectators' attentions: the hats.
From silly to frilly, the race-day hat has become a mainstay (and, to some, a good-luck charm). But, while today's hats can get a bit outrageous, the tradition of hats at the races is a longstanding one. In 1945, LIFE photographer Nina Leen chronicled some of that year's best hats—but the exact details of the story have been lost to time. The photographs in the gallery above never ran in LIFE, and notes about where they were shot were not preserved.
A few clues can be found in the photos: a woman holds a program on which a few horses' names can be read—SAFETY EDGE, WAVERLY, BLUE SWEEP—and some of the features of the track, like the letters U and L on a balcony, are clear. Information about these photos remains a mystery to us (if you have any ideas, you can find us on Twitter at @LIFE) but one thing is clear: when it comes to showing off your hat, the races are the place to win.
Liz Ronk, who edited this gallery, is the Photo Editor for LIFE.com. Follow her on Twitter @lizabethronk.