Commuters have been advised to avoid London Bridge station as thousands head to Greenwich for an equestrian event.
Transport for London (TfL) said the station would be "busy" as 50,000 spectators headed to the equestrian cross country at Greenwich Park.
There were no major problems reported on London's rail and transport network early on Monday morning.
London Mayor Boris Johnson said he was pleased at the way the network was working.
"Obviously the transport, we're pleased with the way it's working so far, everybody at London Bridge was working well, and the Tube is working well," he said.
TfL's director of Games transport Mark Evers said the network had functioned well so far.
"We've got 3,500 of our back-office staff out on the network, dressed in bright pink vests so that if anyone has any questions we can help them get around the network and to where they need to be," he said.
"Nothing can prepare you fully for the Olympics but we're working very hard to make sure that we both get people to the Games but also make sure that London keeps moving as well."
Equestrian events are being held in Greenwich Park, in south-east London.
At London Bridge, platforms one to six, which are used by trains bound for Kent, Sussex and Bedford, will be exit-only from 18:00 until 22:00 BST.
Canary Wharf and Bank stations are also expected to be busy.
In addition to London Underground, Southeastern and First Capital Connect run overground rail services to Kent from London Bridge.
Commuters bound for Kent are being asked to board Southeastern and First Capital Connect services from stations such as Charing Cross, Cannon Street, Victoria or Blackfriars.
TfL and National Rail are also advising spectators to avoid London Bridge and instead take trains from Cannon Street, Victoria or Charing Cross for Greenwich or Blackheath.
Canary Wharf and Bank stations, which are on the Docklands Light Railway (DLR) and are also served by London Underground and London Overground, are being used by Olympics spectators.
The Jubilee Tube line and the DLR, which go up to Greenwich, are also expected to be busy during the evening rush hour.
Mike Brown, London Underground's managing director, said: "After a fantastic Opening Ceremony and weekend of sport, many people will be going back to work on Monday in an Olympic city.
"London Bridge will be exceptionally busy and spectators going to the equestrian event at Greenwich Park are advised to avoid the station."
In addition to the equestrian event, Olympic events will be taking place in the Olympic Park, ExCeL, North Greenwich Arena, Royal Artillery Barracks, Horse Guards Parade, Earls Court, Lord's Cricket Ground, Wimbledon and Wembley Arena.
During the Games, an extra three million journeys will be made on London's transport network every day in addition to the usual 12 million journeys, TfL said.