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The 138th Kentucky Derby starts this Friday, giving celebrities a great excuse to break out their most over-the-top head gear. To celebrate, we’ve rounded up the most statement-making hats in recent history, from Sarah Jessica Parker‘s acorn-topped fascinator and Lady Gaga‘s iceberg design, to Princess Beatrice‘s famous royal wedding topper—a look that launched over 40 Facebook groups. See more outrageous celebrity hats in the gallery now.