At the top of the list, arguably, is Sydney – for it’s magnificent and world-class fireworks display on the city’s sparkling harbour.

Perhaps the most iconic, however, is the ball drop in New York’s Times Square – otherwise known as “the Crossroads of the World”.

It’s where some two million people pack the streets in the core of the Big Apple up to 16 hours before the clock strikes midnight. They come for the spectacle: a free concert featuring some of the world’s biggest stars; an illuminated ball that drops from above a high-rise building, marking the end of one year and the start of the next; and an explosion of confetti, with handwritten wishes written on each piece from members of the public, fluttering through the skies above the bustling streets. To be a part of it and feel the electricity in person is on the bucket list of many people all over the world. The celebration is so popular that revellers arrive in the morning to secure prime position before it fills up and police block access.

But there’s a catch that most tourists who flock to the city for New Year’s Eve are largely unaware of: There are no bathroom facilities. Zilch. No Portaloos, no public rest rooms, and no access to restaurant or bar facilities for non-customers. And in a place so packed that it can take hours just to shuffle from one block to the next – and that’s outside of police pen “lock-in” periods – it’s a discovery many revellers don’t make until it’s too late.

Those privy to the set-up, however, have a secret: adult nappies.

It’s said that the streets of New York City will “make you feel brand new” – a line immortalised in Alicia Keys’ hit song Empire State of Mind.

Just don’t expect to get that on New Year’s Eve when the streets are lined with thousands of adults wetting their “diapers” and thousands more urinating directly onto the street.

“So far, it’s dry, and I’m hoping to keep it that way,” nappy-wearing Dallas teacher Heather Feist, 33, who began lining up at 9.30am, told the NY Post at last year’s event.

Others were not so lucky.

“I’ll definitely need to shower after peeing my pants all day,” Ayame Yamakawa, 22, told the newspaper after travelling 22 hours from Okinawa, Japan, just for New Year’s Eve this time last year.

She had already wet herself once by 2.41pm after lining up at 10am, according to The Post.

At a previous NYE street celebration in Times Square, Jeryl Lippe, from New Jersey, got a bad case of karma after she smuggled vodka into the alcohol-free zone inside a water bottle. She didn’t eat anything other than a breakfast bagel and didn’t have her illicit drink until the end of the day, she told local The Post. But, “by the time it was turning midnight, I had drunk a lot and was desperate to go to the bathroom,” she continued. “I tried to find some place to go – hotels, restaurants,” she said, but she was denied.

Chuck Pappas travelled from interstate for NYE at the “Crossroads of the World” in 2014, at the time telling Business Insider: “We have Red Bull, energy shots, lots of snacks, water, playing cards, we’re all wearing several layers and … we’re all wearing diapers.”

Brian Alvarado, from Westchester, New York, last year recalled how one of his friends gave up and urinated in the street, adding, “I’ve heard stories of people who wear (adult) diapers.”

megan.palin@news.com.au | @Megan_Palin