A five-day strike on the Southern Rail network has started which will see 40% of normal services cancelled for the majority of this week.
Southern and the Rail, Maritime and Transport Workers union (RMT) are involved in a dispute over the role of guards. Talks to try to reach an agreement at the Advisory, Conciliation and Arbitration Service (Acas) failed last week, the RMT union said.
The strike will begin on Monday 8 August, with hundreds of trains cancelled across south east England. Here is how to get into London during the walkout:
Which routes are running a limited service?
A limited service will run between 7.30am and 6pm on the following routes:
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 - Christ's 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)
Will there be a replacement bus service?
There will be a replacement bus service calling at Lewes, Southease, Newhaven Town, Newhaven Harbour, Bishopstone and Seaford.
Will taxis be paid for by Southern?
No, Southern has said there are not enough buses or taxis available to provide a service across the entire route.
Will I be able to use my ticket on other train operators' services, the tube or London buses?
Thameslink, Southern and Gatwick Express will accept each other's tickets on the strike days.
Tickets that are normally valid on other routes - such as Oyster on the Tube - will be valid as usual.