It's just four days before the London Olympics begin and there are further concerns about how the transport system will perform when the Games get underway.
There have been severe disruptions to three of the main rail links to the Olympic Park in east London and notice of some strike action by transport workers,raising anxiety levels in the British capital.
The Central Line was closed for a period because of a passenger was on the tracks, the Jubilee Line had delays, caused by faulty platform-edge doors, and the Overground's problems were due to a signalling failure.
The labour union, RMT, also announced industrial action by staff in some parts of the city's transport network during the Games, to demand bonuses in recognition of the extra work involved.
The RMT says staff from South West trains would refuse to work overtime throughout the Games, while staff at the company that runs bicycles-for-hire in the city would take similar action during the first Olympic weekend.
Some staff at Transport for London, including those manning information telephone lines, would also strike for short periods during the opening weekend.