Police say they were taken by surprise by the number of people who turned out to celebrate the opening of the Rugby World Cup on the Auckland waterfront on Friday night.
An official number has not been released but Superintendent Brett England says it may have been as high as 120,000.
Police used the loud speakers at Eden Park to ask people leaving the opening game to avoid going back into the city.
Superintendent England says he increased the number of police at the waterfront when he realised the crowd was going to be bigger than expected, and later bolstered them further with officers from Eden Park.
People at both events were largely well behaved. Fifty people were arrested in the central city.
Fourteen people were evicted at Eden Park. One arrest was made there.
Ambulance officers treated 80 people at the waterfront and 75 people at Eden Park for minor alcohol-related conditions.
Thirty people were taken to hospital from the waterfront and three from the stadium.
The unprecedented number of revellers proved to be too much for public transport networks.
There were delays to buses for most of the night and ferry services stopped altogether when Queens Wharf became too full.
Train delays caused some passengers to miss the opening kick-off at Eden Park.
Extra buses were brought in to clear the post-match crowd and most people had moved on within 70 minutes.
Auckland Transport says it will ask Veolia, the train operator, for an explanation.
Motorways were free-flowing throughout the night.