London 2012: Tube line to Games Park disrupted
A key Tube line which goes to the Olympic Park suffered severe delays after a signal failure on what is said to be the busiest day so far.
Central Line was suspended between Liverpool Street and Leytonstone for over an hour during the rush hour due to a signal failure in Bethnal Green.
There were also long queues at St Pancras International station for the Javelin to the Olympic Park.
Transport for London said more than 200,000 people will head to Stratford.
The disruption on the Central Line led to a knock-on effect at St Pancras but services are now running normally.
A Transport for London (TfL) spokesman said: "We are advising spectators going to Stratford to use the wide range of other lines serving the Olympic Park, including national rail services from Liverpool Street and the District and Hammersmith & City lines, where passengers can use West Ham station with a short walk along the Greenway to the park."
More than 200,000 people will be at the park, including people heading to the 80,000-capacity Olympic Stadium for the start of athletics events.
TfL said Docklands Light Railway, Jubilee line, Central line and roads to the Olympic Park would be exceptionally busy on Friday and urged people who are not going to the Games to avoid the area.
Westfield shopping centre in Stratford will also be closed to shoppers until 17:00 BST on both Friday and Saturday to cope with the crowds.
Events will take place at the Olympic Park, ExCeL, North Greenwich Arena, Greenwich Park, Royal Artillery Barracks, Horse Guards Parade, Earl's Court, Lord's Cricket Ground, Wimbledon and Wembley Arena.
Friday and Saturday is expected to be the "busiest days of the Games so far", London's Transport Commissioner Peter Hendy said.