Passengers were hit by delays and disruption today as they tried to get to work or travel in London after a strike went ahead over Tube ticket office closures.
Reduced services were running on most lines, while many Tube stations were closed, causing travel chaos.
Members of the RMT and TSSA unions walked out at 9pm last night for 48 hours in protest at the closure of all ticket offices, with the loss of 950 jobs.
Services were hit last night immediately after the strike started, and disruption is set to be widespread today.
Queues started building up at bus stops before dawn as commuters switched to other forms of transport.
Some workers decided to drive into the capital, making roads busier than normal.
Train passengers were also having problems because of a return to the wet and windy weather which has devastated travel across the UK.
Southeastern trains said the forecast weather, after the wettest January for a century, presented a risk of further flooding, landslips and falling trees.
Network Rail has put in place a 40mph speed restriction across parts of the Southeastern network.
Picket lines were mounted across the capital today outside Tube stations, while the two sides in the dispute continued to argue over the ticket office closures.
Politicians have condemned the industrial action, with Conservatives again calling for changes to employment laws covering the numbers voting for strikes in a ballot.
London's mayor Boris Johnson called the strike "pointless" and urged the unions to call it off and return to talks.
Bob Crow and Manuel Cortes, leaders of the RMT and TSSA unions, accused the mayor of refusing to meet them to discuss the ticket office closures.
As the row raged, commuters and other passengers faced travel misery until services return to normal on Friday.
Another 48-hour strike is planned from 9pm next Tuesday.
Business groups warned the strikes will cost London's economy tens of millions of pounds.
London Overground trains became so crowded that passengers were unable to board them at stations in north-west London.
To add to the chaos a packed Overground train at North Wembley was delayed after a passenger pulled an emergency cord.
Mr Crow said: "As we expected the action is rock solid this morning and has reduced the network to a skeleton service with only a few ghost trains running through closed stations.
"That is simply a reflection of the staff anger at attempts to bulldoze through cuts to jobs, services and safety which would reduce the Tube to a dangerous, hollowed-out shell.
"No one can now question the determination of the Tube workforce in the face of the mayor's cuts plans.
"I am making it clear again this morning that the unions remain available for talks at any time aimed at resolving this dispute and we just hope that offer is taken up.
"We have set out a clear route to move this issue forwards and we await a response from LU."
LU said the Northern line was running end to end, with some station closures, and reported a widespread service on the District line, with other lines running as predicted with reduced trains.
A Transport for London spokesman said: "Many thousands of London Underground and TfL staff are working flat out today to help our customers and to keep London working in the face of this pointless action by the RMT and TSSA leaderships.
"We thank Londoners for their patience during what will undoubtedly be some difficult journeys today.
"Our bus, rail, DLR, tram and river services are all operating well while other Londoners will be making use of our cycling and walking networks.
"Our staff, including volunteers from support functions, are at main transport hubs to offer help and advice, including handing out maps and giving directions for other services.
"We will continue to run as many trains as we can, keep customers informed about how all our services are running and ensure we keep London moving and open for business."