Usually busy stations were deserted on Tuesday morning as Transport for London warned, "only travel if your journey is essential."
Millions of Londoners are suffering disruption as the largest rail strike for a generation cripples services.
Transport for London (TfL) warned against travel on Tuesday, 21 June, as Tube workers launched a strike to coincide with the first day of a series of rail strikes spread across this week.
Severe disruption affected services throughout Tuesday, when many stations and lines closed.
Transport bosses were warning Tube passengers that the few services running were expected to be busy with commuters, with long queues for bus services.
Drivers were being warned to expect a surge in traffic as train passengers switch to road transport during the rail strikes throughout this week.
Figures from technology firm TomTom showed congestion levels increased in London from 77% a week ago to 98% today.
Members of the Rail, Maritime and Transport union (RMT) on Network Rail and 13 train operators are striking this week on June 21, 23 and 25, causing huge disruption to services.
The RMT and Unite members are striking on the London Underground on Tuesday, in a separate dispute.
Above: London Underground trains in the depot as strikes get underway
The rail strikes are being described as biggest outbreak of industrial action in the industry in a generation - with half of Britain’s rail lines closed during the strikes on June 21, 23 and 25.
TfL is advising passengers who must travel during Tuesday's strike on any running services to finish their Tube or rail journey by 6pm.
Which lines are impacted by the Tube strike on Tuesday?
On Tuesday 21 June, national rail and most TfL and national rail services will be severely disrupted or not running.
That includes all Tube lines: Circle Line, Jubilee Line, District Line, Hammersmith and City Line, Metropolitan Line, Northern Line, Central Line, Victoria Line, Bakerloo Line, Piccadilly Line, and the Waterloo & City Line.
The following will also be disrupted due to the scale of the strikes:
The Elizabeth line
Above: Elizabeth Line trains in the depot as strikes get underway
Is the Elizabeth line running during the Tube Strike?
While the Elizabeth line, which operates on TfL Rail as part of the Crossrail scheme, will still be running, TfL is warning its services will still be impacted on every strike day, due to the delays across the network.
For passengers using the Elizabeth line on the Tube strike day of Tuesday, 21 June, TfL has issued the following on which sections will be affected and when.
The eastern section of the Elizabeth line (London Liverpool Street-Shenfield) will be running a reduced service and shorter operating hours. Passengers are advised to complete their journeys by 4pm.
The central section (Paddington-Abbey Wood) will be running a reduced service, and journeys should be completed by 6pm.
The western section (Paddington-Heathrow and Reading) will be running a reduced service and shorter operating hours, and journeys should be completed by 4pm.
On the national rail strike days of Thursday 23 and Saturday 25 June, the central section of the Elizabeth line will be fully open and running.
However, TfL says the eastern and western sections will both be running a reduced service and operating hours - with a late start and early shift - and journeys should ideally be completed by 4pm on those two days.
Also on Thursday 23 June and Saturday 25 June, there will be also no service from Queen’s Park to Harrow & Wealdstone on the Bakerloo line and on the Richmond and Wimbledon branches of the District line services will only operate between 07:30 and 18:30.
Will the DLR and Overground be affected by the Tube and rail strikes?
The DLR will not be part of the strikes, but will be affected and running reduced services.
London Overground services will run between 7.30pm-6.30pm on each strike day, and between 7.30-6pm on Thursday 23 June and Saturday 25 June.
Thameslink will also be open, but running on a reduced timetable.
TfL is warning of pressure on running services caused by the closure of other routes.
Will airport trains be running?
The Heathrow Express, which runs regular services to Paddington Station, will be running but on a reduced timetable.
The Gatwick Express will not run during the rail strikes.
TfL has also advised buses will be extremely busy with queues to board.
What dates will the rail strikes affect London?
Transport bosses are warning the three days of rail strikes will have knock-on effects across the entire week.
As part of nationwide rail strikes, around 50,000 railway workers will walk out on Tuesday 21 June as part of their triple-day strike action, following by strikes on Thursday 23 June and Saturday 25 June.
Unions are warning the walk outs will affect the national railway network for the entire week.
Disruption can therefore be expected on Wednesday June 22 and Friday 24 June, when there are no strikes planned, as trains will not be in the correct positions due to the action taken on the days before.
Transport authorities are warning fewer than one in five trains are likely to run on strike days, only between 7am and 7pm, and probably only on main lines.
Will Tube or rail journeys on Wednesday be affected?TfL is warning of a knock-on effect the day after the Tube strike.
No Tube services will run before 8am.
Commuters are warned to avoid making any Tube journeys until mid-morning as disruption is likely to continue.
There is expected to be reduced service on the London Overground and Elizabeth line until mid-morning.
Which lines are affected by the national rail strike?
Britain’s train operators have released detailed information about any services they intend to run during this week’s rail strikes.
Rail workers are walking out on Tuesday, Thursday and Saturday, but there will also be disruption on Wednesday, Friday and Sunday which could affect journeys to and from London, and to onward destinations.
Here is a breakdown of each rail operator’s plan for strike days:
Avanti West Coast
A limited service of around a quarter of the normal timetable will operate, and only between 8am and 6pm.
A number of routes will not be served, such as to North Wales, Stoke and Edinburgh.
The operator has suspended ticket sales for travel between Tuesday and Sunday to “help reduce disruption and overcrowding”.
It will operate fewer than a third of normal services, only between 7.30am and 6.30pm.
This will include two trains per hour from London Fenchurch Street to Shoeburyness via Laindon, and the same frequency from London Fenchurch Street to Pitsea via Rainham.
No trains will run via Ockendon or Chafford Hundred.
All departures are cancelled between Monday and Friday.
No trains will run north of Banbury or to Oxford between Tuesday and Saturday.
Services will be suspended on “most routes” on strike days due to “extremely limited availability of staff”.
Timetables are being finalised but there will be a “significantly reduced service” on strike days.
East Midlands Railway
Services will be reduced between Tuesday and Sunday.
Just one train per hour will run in each direction on most routes.
No service on strike days.
A Sunday service will run on the days after the strikes, with late starts and early finishes.
On strike days it will run a “limited service”.
Very few trains on strike days, with no services east of Ely to King’s Lynn.
An amended Sunday service will be in place on the days after strikes.
Great Western Railway (GWR)
Services will be “severely affected” between Tuesday and Saturday.
Timetables for those days have not yet been released.
On strike days the firm will not run any trains on its regional and branch lines.
A “very limited service” will operate on some routes to and from London Liverpool Street for part of the day.
A reduced frequency service will be in place, with later first trains and earlier last trains.
On strike days, trains will only run between Doncaster and London King’s Cross.
London North Eastern Railway
Around 38% of usual service levels are planned.
Trains that do run “are likely to be very busy”.
London Northwestern Railway
Services on strike days will be “very limited”.
This includes just two trains per hour between London Euston and Northampton, and one per hour between Birmingham New Street and Northampton.
No trains will operate between London Euston and Crewe.
There will be “some disruption” to services throughout the week.
There will be a “significant impact” on services.
Passengers are urged “not to travel” between Tuesday and Sunday as services will be suspended “on most routes” during strike days, and there will be a “significant impact” on non-strike days.
No trains will run north of Glasgow or Edinburgh on strike days.
Just two trains per hour will run between the cities via Falkirk.
South Western Railway (SWR)
A “severely limited service” will run between 7.15am and 6.30pm on strike days, and only on some routes.
This includes only four trains per hour between London Waterloo and Woking, two per hour between London Waterloo and Basingstoke, four trains per hour in each direction between Waterloo and Woking, and two trains per hour in each direction between Waterloo and Southampton.
Trains will not stop at all stations on these routes, SWR is warning.
Island Line services will not be affected by the industrial action. There will be no SWR services across the rest of the network.
Significant disruption is also expected on Wednesday 22, Friday 24 and Sunday 26 June, when the network will not be operational before 07.30am and a Sunday level of service will operate throughout the affected days.
Most stations and routes will be closed on strike days, and a “severely reduced service” will operate elsewhere.
Much of the network will be shut down on strike days.
Services will run on the Brighton Mainline to London Bridge and London Victoria, with additional trains from Tattenham Corner, Epsom Downs, Sutton and West Croydon, via Crystal Palace.
An amended Sunday service will operate after each strike day.
A reduced frequency will be in place, with later first trains and earlier last trains.
There will be far fewer trains than normal on strike days.
Services will be split north and south, with nothing running between London St Pancras and London Bridge.
An amended Sunday service will operate after each strike day.
There will be a “significant reduction in available services” on strike days.
Several stations will be closed, such as Middlesbrough, Scarborough and Selby.
There will also be significant disruption on Wednesday and Friday.
Transport for Wales
The majority of lines will be closed on strike days, with reduced frequencies on those that remain open.
West Midlands Railway
The industrial action will have a “considerable impact on the number of trains” that run on strike days.
There will also be a “very limited service” on Wednesday and Friday.
Why are the Tube workers striking?
London Underground staff who are members of the RMT union are striking in a row over jobs and pensions separate to the nationwide rail strikes.
Unite union members who work for other branches of TfL will also walk out.
TfL insists no decisions or proposals have been made, after United said workers were striking over pay and plans to cut pensions.
Which events could be affected by this week's Tube and rail strikes?
The strikes threaten widespread travel disruption during a number of major events, including concerts, Test match cricket and the Glastonbury festival.
People travelling in and out of London to the following events are advised to consider alternative travel options.
Glastonbury starts on 22 June.
England's New Zealand Test match in Leeds on 23 June.
The British Athletics Championships in Manchester between 24-25 June.
Sir Elton John's London Hyde Park gig on 24 June.
The Rolling Stones' Hyde Park gig on 25 June.
Commonwealth Heads of Government meeting in London on 24-25 June.
Armed Forces Day on 25 June.
See the full list of railway services affected by the three days of rail strikes here.
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