Women face being turned away from the Royal Enclosure during Royal Ascot if they wear off-the-shoulder or strapless tops
Halter necks are also a no-no
Spaghetti straps are considered unsuitable
Midriffs "must be covered"
Mini-skirts are considered "unsuitable"
Trouser suits are acceptable but only if they are "full length and of matching material and colour"
Bare legs are frowned upon
"Knickers," the guide says. "A definite yes, but not on show please ladies."
Ladies must wear hats...
...or "substantial fascinators"
The guide also warns that streaky tan lines are "a total fashion faux pas". Other faux pas to avoid in the Royal Enclosure are chewing gum and talking on a mobile phone