Royal Ascot - Day 3
Credit: Horsephotos/Frank Sorge/Getty Images

Horse races, polo matches, weddings, boat races, the Queen’s birthday parade… As an American living in London, there’s no shortage of summer social events to don your glad rags and wear a proper hat or jaunty headpiece. And the grand dame of them all is the Royal Ascot, a 300-year-old tradition that is known as much for its spectacular people-watching and outrageous headwear as it is for the world-class horse racing.

And though the hats and headpieces on view during the course of the five-day event can be quite over-the-top, the Ascot has a very strict, detailed dress code (dependent on your ticket level). This year, I was lucky enough be invited to watch the races from the Grandstand, which is the upscale public enclosure with a formal dress code of suits for men and dresses of a modest length for women with hats or headpieces (with a base measuring four inches or more) worn at all times.

And it’s not just for show: The Brits can be real sticklers for formality and protocol, especially when the Royal family is involved. Royal Enclosure ticket holders—the members-only section with the strictest dress code of all, as it surrounds the Royal Box where the Queen sits—receive a 20-page booklet outlining the rules. There’s even an instructional dress-code video on its website.

I was not about to get turned away at the gate. So though it felt a bit silly and school marm-ish, the night before Ascot, I dutifully broke out my ruler and measured my blue brocade dress straps (1 ¾ inches, phew!) the base of my headpiece (which just made it to the 4-inch mark, yes!) and scrutinized my dress length with the voracity of a Catholic nun at a middle-school dance. I was now starting to understand why Kate Middleton always plays it so safe.

Arriving at Waterloo station is a flurry of hats and headpieces. I don’t even bother to look at the departures board to Ascot, I just follow the hats. (Fun fact: I learned during my sartorial research that to be taken seriously in the millinery scene, one must never use the word “fascinator” which Tatler declared to be “worse than the f-word” in their guide to Ascot. I turned to milliner William Chambers to find out why. “They became so ubiquitous in the 2000s that they now suggest a cheap, last-minute thought and token gesture rather than really thinking about the outfit and the occasion.”) Inside the train, it’s all men in three-piece suits, ladies in colorful hats and the sound of Champagne corks popping. The strict dress code does lend a sense of occasion, even on a commuter train out to the English countryside.

Royal Ascot embed
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Arriving at the gates of Ascot (pictured, above), I have a chat with the dress code assistants; a friendly group of smartly dressed men and women holding baskets of accessories for under-dressed guests. There’s a remedy for almost any fashion faux pas. For those baring a bit too much skin up top, they’ve got pashminas and tank tops in a variety of colors. For skirts that fail to meet the modest requirement, “skirt extenders,” which look like slips or petticoats, are offered to guests. There’s even a rack of women’s hats and headpieces and men’s ties, blazers, vests and top hats to borrow for a small deposit.

For such a formal event, the dress code assistants are surprisingly friendly and democratic. “Our goal is not to turn anyone away,” one assistant tells me. “We want to help them get what they need to be admitted in and feel comfortable.” He then ominously adds, “We do watch everyone on CC TV once they’re admitted to make sure they’re still following the dress code. It’s all about showing respect to the Queen.”

And then, with ticket in hand, I gained entry, no aid from the dress code assistants required. It was a glorious and perfectly British Day.

Valerie Denny is an American writer living in London. Follow her on Instagram and Twitter.