But when travelling on the tube or train, it is not every day that you have an encounter with hundreds of briefs.

This was the case today as thousands of bare-legged people around the world took part in the international ‘No Pants Subway Wide’.

Scantily-clad riders in 60 sixties around the globe braved the weather and some stares from fellow commuters for the annual celebration.

It started off as a prank by comedy group Improv Everywhere in 2002, bemusing a few embarrassed commuters, but has since grown into a global phenomenon.

Trains and trams in major cities from Brussels to Beijing and Sofia to Sydney were awash with bare legs and briefs on Sunday as pranksters travelled trouserless.

The event began in Australia, where commuters got to cool off during the warm summer conditions by stripping down to their under garments.

Commuters in London, Berlin and Hong Kong then braved public transport without trousers in the stunt, which has worldwide since its first staging in New York 12 years ago.

The rules are fairly straightforward.

Underpants must be worn and, although flashy designs are allowed, organisers prefer those involved to look – at least from the waist-up – as though they are going about their daily lives.

This is to increase the impact the participants have on the unaware bystanders.

In the inaugural event ago only seven people took part, but now thousands in major capital cities around the globe participate in what organisers call a ‘celebration of silliness’.

Uniforms and business suits are encouraged to amplify the lower-half effect as are props – bicycles, prams, shopping bags or a briefcase.

Participants are also forbidden from speaking to one another and are instructed to bring ‘any activity you might normally perform on the train: newspaper, book, sewing kit.’

‘If questioned, you do not know any of the other pant-less riders. Tell folks that you ‘forgot to wear pants’, organisers told participants ahead of the Sydney ride.

‘Insist that it is a coincidence that others also forgot their trousers. Be nice, friendly and remain calm.’

In Sydney, a small but dedicated group dropped their trousers on the city circle loop train, packed with bemused weekend sightseers on a busy summer’s day, then switched routes for a return trip to Bondi.

There was a no trousers tram ride in southern Melbourne and Adelaide and people also went pants-less for a train trip in northern Brisbane.

On a busy Hong Kong subway train around 40 people, including Australian Bess Hepworth and her 18-month-old son, joined in the fun.

‘It’s the first time he will be publicly taking off his pants, although he does it regularly already,’ the 37-year-old said.

In Beijing a handful of trouserless people took to the Chinese capital’s fast-growing subway, drawing confused glances from onlookers.

‘I want to show that (Chinese people) are internationalised now,’ said 22-year-old Huang Li, wearing blue underwear decorated with dots. ‘People say I’m a psycho,’ she added.

Improv Everywhere expects some 4,000 participants in this year’s New York event, with more than 60 other cities taking part including Paris and London.

The annual event steadily grew each year with more and more people choosing to take part.

But it nearly hit the buffers in 2006 when the stunt was halted by a New York policeman. Eight passengers were handcuffed in their underwear and taken into police custody.

A judge later threw out the case because it is not illegal to wear just your underwear on the Subway.

The No Pants event went global in 2008 with Adelaide in Australia joining eight American cities in taking part in the stunt.

The event in 2012 saw tens of thousands of people daring to bare their underwear in 59 cities in 27 countries around the world.

Source: dailymail.co.uk

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