Police arrested 17 people and shut six London Underground stations during a chaotic night of partying to mark the last day of drinking on the Tube.
A booze ban is now in effect on the Tube, London buses, Docklands Light Railway and tram services across the capital.
Passengers are no longer allowed to drink from or carry open containers of alcohol.
The measure was announced earlier this month by new London mayor Boris Johnson.
But a night that started in a celebratory mood soon turned sour as thousands of revelers poured into London's Tube stations.
Four train drivers and three other London Underground staff were assaulted, one police vehicle damaged, two officers assaulted and another injured.
A spokesman for British Transport Police said 17 people were arrested for offences like assault, drunk and disorderly, assault on police, public order-related offences and drug offences.
Eyewitnesses said there were nightmarish scenes on trains and in stations as thousands of drunken partygoers began fighting and vomiting as the night drew to a conclusion.