London Pete Duffell stood on the subway platform late Saturday, swigging a cold beer and ready to party.
Duffell, 24, a professional scuba diver from Kent, and two buddies - one with his hair dyed green for the occasion - hauled three plastic bags filled with beer and wine onto a Circle Line subway train.
At midnight Saturday, drinking on London's Tube would suddenly be banned for the first time in the storied history of the world's oldest underground train system. Duffell and thousands of others, many wearing tuxedos, Mexican sombreros and Darth Vader masks, decided to hold one last public guzzle-a-thon to mark the moment.
So in super-octane parties organized largely on the social networking Web site Facebook, thousands of raucous revelers transformed the Tube into a huge, sweaty party all Saturday evening. They sang, hooted, ripped off their shirts in the swampy heat and consumed massive amounts of alcohol - some through funnels - like there was no tomorrow, which, in the case of drinking on the Tube, there wasn't.
"I am not in favor of anarchy, I am not trying to cause harm; we are just here to have a laugh," said Duffell, who said he started his "Tube crawl" at 2 p.m. and planned to go until the last legal second.
"If you tell a British person not to do something, if you say no, we will do it even more," said Duffell, offering a drink to six passing police officers, who ignored him - at least for a few more hours.
When Mayor Boris Johnson took office this month, one of his first acts was to ban, as of June 1, the age-old London tradition of boozing on subways and buses.
In sharp contrast to the United States, it is perfectly common to see people drinking alcohol on London public transportation. In fact, it is legal to drink in almost any public place in the city.
"People have been consuming alcohol in public places in this city longer than the United States has been around," said Tim O'Toole, an American who is managing director of the London Underground. "This is much more of a drinking culture, so a change like this would seem more dramatic."
With a stroke of his mayoral pen, Johnson created a debate that cuts to the heart of a society that cherishes drinking the way Americans revere shopping.
"This has hit a nerve. People are asking about civil liberties," said Stephen Emslie, 27, who announced a Tube drinking party on Facebook, prompting more than 4,000 people to sign up.
"A part of British culture is about drinking," he said. "I had no intention of throwing a big party. It seems people are using this as a way to express the way they feel."
Supporters of the open-container ban said it is a centuries-overdue, common-sense move that will reduce assaults and other crime. But critics said Johnson's first official decree was a decidedly un-British spasm of politically correct overkill.
"They are taking away our freedom and liberties," said Duffell's green-haired friend, Marek Tomecki, as he slurped a Baileys Irish Cream and milk.
"When I get drunk I don't beat people up on the Tube," said Tomecki, 30, a New Zealander who lives in London. "Aren't there bigger issues to worry about? I came to liberal England to enjoy. I didn't come here for the weather."
The Tube is one of London's most renowned attractions, transporting more than 3.2 million commuters and tourists every day. More than 6 million ride the buses.
But at night the character of the Tube and London buses often turns much more rough and menacing, as people spilling out of pubs continue their drinking on the way home.
Johnson said the ban fulfills a campaign pledge to make London's public transport safer and crack down on the drunkenness that leads to assaults and other crime. Duffell, for example, said he had been mugged "a couple of times" on London buses by people who had been drinking.
The union that represents most Tube and bus workers has criticized Johnson for passing the ban without consulting its members, who will now have to ask people to throw away their drinks.
"Violence against our members is already a major problem, particularly from people who have been drinking," said union chief Bob Crow. "Perhaps the mayor will come out with his underpants on over his trousers like Superman one Saturday to show us how it should be done."
O'Toole said he believed that people would adjust their habits to the ban as easily as they adapted to a ban on smoking. "These things become self-policing," he said.
Saturday night, the mood on the Tube was a cross between Halloween, an Irish wake and a sticky, sloppy fraternity party. Tube trains were packed with sweaty partiers, including some who hung by their feet from the handrails on the ceiling.
Many dressed as Johnson, wearing white-blond wigs to mimic the mayor's memorable head of unruly platinum blond hair.
"For the British public, alcohol is an important release, it's part of how we work," said Roy Halcro, 20, a pub manager wearing a Johnson-esque wig and pink tie.
"It's an infringement on our civil liberties not to be able to drink a legal substance on the Tube," he said, as several hundred people on his train car started pounding on the ceiling and chanting obscenities about Johnson.
Organizers of the Tube parties repeatedly reminded people to maintain a fun atmosphere, and not to resort to the sort of recreational brawling so common to pub closing times around Britain.
Susanna Marshall, 45, brought her 5-year-old son with her to bear witness to the last day of legal boozing on the Tube.
"I wanted to show him it is okay," she said, sipping pink zinfandel from a wine glass. "We were once okay. He will say he was here. People have been drinking since the Stone Age. This won't change much."