A five-day strike has begun on the Southern rail network, during which just 60% of its normal timetable will run.
Southern and the Rail, Maritime and Transport Workers union (RMT) are involved in a dispute over the role of guards and talks to resolve the situation broke down last week.
When is the strike?
The strike will take place from Monday 8 to Friday 12 August.
Southern said in a statement: "Southern expects to run almost 60% of its normal timetable (or two-thirds of the temporary revised timetable) from Monday 8 August to Friday 12 August inclusive.
"There will be extra staff at stations to help passengers and arrangements in place for passengers to use alternative transport providers."
Which routes are not running?
No Southern trains will operate in either direction on the following routes:
- Clapham Junction to Milton Keynes via Kensington Olympia
- Dorking to Horsham
- Oxted to Uckfield
- Haywards Heath to Lewes
- Preston Park to Hove
- Lewes to Seaford
- Eastbourne to Ashford International via Hastings (Southeastern services will operate between St Leonards Warrior Square and Hastings as normal)
- Chichester to Portsmouth Harbour and Southampton Central (South West Trains and Great Western Railway services will operate between Havant and Portsmouth Harbour/Southampton Central as normal)
- Redhill to Tonbridge
- Redhill to Reigate (Great Western Railway services will operate on this route as normal)
- Earlswood, Salfords and Faygate stations will not be served
- Guildford to Leatherhead (South West Trains services to/from London Waterloo will still operate)
- Sutton to Streatham via Wimbledon (Thameslink services will still operate)
- Crystal Palace to Beckenham Junction
- West Norwood to Tulse Hill
Which routes are running a limited service?
A limited service will operate in both directions from approximately 07.30 to 18.00 on the following routes. Southern has warned these services are expected to be extremely busy and cannot guarantee there will be space to travel.
- London Bridge - Norwood Junction - East Croydon - Sanderstead - Riddlesdown - Upper Warlingham - Woldingham - Oxted - Hurst Green - Lingfield - Dormans - East Grinstead
- London Victoria - Clapham Junction - East Croydon - Redhill - Gatwick Airport - Three Bridges
- Three Bridges - Crawley - Ifield - Littlehaven - Horsham - Christs Hospital - Billingshurst - Pulborough - Amberley - Arundel - Ford - Barnham - Chichester (note that the last trains from London to Three Bridges connecting with this route will be at approximately 16:30 to some stations)
- Brighton - Hove - Aldrington - Portslade - Fishersgate - Southwick - Shoreham - Lancing - East Worthing - Worthing - West Worthing - Durrington - Goring - Angmering - Littlehampton - Ford - Barnham - Bognor Regis (note that the last connecting trains from London to Brighton will be at approximately 16.30)
- Brighton - London Road - Moulsecoomb - Falmer - Lewes - Glynde - Berwick - Polegate - Hampden Park – Eastbourne (note that the last connecting trains from London to Brighton will be at approximately 16.30)
What has been said by Southern and the RMT?
Govia Thameslink Railway passenger service director, Angie Doll, said: "We are sorry that our passengers once again look set to suffer further disruption because of the RMT. The union must call this action off by Thursday afternoon if we are to avoid having to put in Monday's strike timetable."
RMT general secretary, Mick Cash, said: "This action has been forced on us by the arrogance and inaction of Govia Thameslink and the Government who have made it clear that they have no interest in resolving this dispute or in tackling the daily chaos on Southern.
"Our fight is with the company and the Government who have dragged this franchise into total meltdown. We share the anger and frustration of passengers and we cannot sit back while jobs and safety are compromised on these dangerously-overcrowded trains."