The most embarrassing behaviour at Derby Day in Australia

A man tries to do a headstand on Derby Day at Flemington Racecourse in Melbourne. Photo / AAP

Derby Day is a Spring Carnival favourite. Around 90,000 racegoers arrive in elegant black-and-white outfits to enjoy some trackside bubbles in the sun.

But even a barely legal 18-year-old can tell you that copious amounts of alcohol, too much time in the heat and little food is a dangerous combination.

It seems many have no intention of leaving with their dignity intact. Saturday was a busy day for security, police and paramedics in Melbourne, as the glamorous event descended into bedlam.

Special security guards searched public areas for alcohol brought to the racetrack, hidden in water bottles, zip-lock plastic bags, and even Pringles cans.

Straw hats, sunscreen and stubbie holders were the biggest sellers as punters gathered beside the track. By 3pm many were barefoot, and stripping off their clothing under the hot spring sun.

One man collapsed trying to do a headstand, as his mates egged him on. Another lay down among the rubbish, nursing his head. One guy even found a cricket bat, and started playing with the rubbish and some impromptu wickets made from sticks.

Of course, a few were violent, and there was always going to be vomit. Police made numerous arrests while St Johns Ambulance paramedics were kept busy treating drunk and dehydrated punters.

A woman in a stylish black dress and strappy heels was escorted from the track after lying down in the middle of a public area, giggling. She was still doubled-over with laughter as security dragged her to her feet and carried her out.

A female racegoer is escorted from the racetrack by security. Photo / Getty Images

Craig Lovett is responsible for the massive clean-up. He told news.com.au his team clears an estimated 250 tonnes of rubbish from Derby Day, which is more than the other three days of the Spring Carnival combined.

"Sometimes we'll find the odd person who has left themselves in a car park or a marquee," he said.

They also discover "lots and lots" of underwear as well as "stacks" of shoes and hundreds of pairs of sunglasses.

"One year we found an entire suit - the shirt, tie, shoes, socks. I have no idea what happened to the guy".

Punters risk hefty on-the-spot fines of $622 for public drunkenness, or $777 if they're drunk and disorderly.

Two people were arrested for "upskirting", or photographing underneath women's dresses and skirts, but police have released no further details.

A man carries a female racegoer home following 2016 Derby Day at Flemington Racecourse. Photo / Getty Images