If you have the undoubted pleasure of watching from the Royal Enclosure, then a real effort will have to be made.

BBC: Kitted out for Royal Ascot

The 2015 guidelines on dress code, detailed in full on the Royal Ascot website, are pretty prescriptive, especially for racegoers in the higher echelons of the Royal Enclosure.

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In an effort to keep with the times, Ascot did experiment in the Swinging Sixties - in 1968, men were permitted to wear lounge suits in the Royal Enclosure on the Friday of the meeting.

BBC: Kitted out for Royal Ascot

Next, you will see the Royal Enclosure, a loop of road with several sets of ruins, and beyond that, the Queen's bath, a faded building with sumptuously curved arches inside, surrounding a now empty bathing pool.

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Players past and present, including Martina Navratilova and Billie Jean King and current champions Serena Williams and Roger Federer, met the Queen in the members' enclosure ahead of her arrival in the royal box on Centre Court.

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