When is the UK train strike and which lines are affected?

Watch: Britons urged to prepare for week of disruption during rail strikes

The biggest rail strike in a generation will bring massive disruption across the UK this week.

Half of Britain's rail lines will be closed during the three-day walkout, which will cripple services for most of the week.

More than 50,000 members of the RMT union will take part in the strike after talks failed to resolve a bitter row over pay, jobs and conditions.

The industrial action will spark travel chaos for masses of music fans heading to Glastonbury Festival which starts on Wednesday.

Industry group UK Hospitality has warned the strike could cost tourism and leisure industries more than £1bn.

Here is everything we know about the walkout so far.

When is the rail strike?

The rail strike will take place on Tuesday 21, Thursday 23 and Saturday 25 June. However, the national network will likely be disrupted for the entire week.

The number of passenger services on the strike days is expected to be limited to around 4,500 compared with 20,000 normally.

Lines will only be open between 7.30am and 6.30pm, meaning services will start later and finish earlier than usual.

National Rail urged passengers "who must travel" to "plan ahead" to ensure they can complete their journeys within this window.

The walkout is being staged by members of the R union at Network Rail and 13 train operators.

London Underground workers will stage a strike on 21 June in a separate dispute.

Major events taking place this week include:

• Glastonbury Festival (22-26 June, Somerset)

• England vs New Zealand cricket Test (23-27 June, Leeds)

• Sir Elton John concert in Hyde Park (24 June, London)

• Commonwealth Heads of Government meeting (24-25 June, London)

• British Athletics Championships (24-26 June, Manchester)

• Rolling Stones concert in Hyde Park (25 June, London)

• Armed Forces Day (25 June, UK-wide)

Network Rail said no passenger services will serve locations such as Penzance, Bournemouth, Swansea, Holyhead, Chester and Lancashire.

There will also be no passenger trains running north from Glasgow or Edinburgh.

Open lines include the West Coast Main Line from London to Scotland via locations such as Birmingham and Manchester.

Why are rail workers striking?

The RMT is locked in a bitter dispute with rail companies over jobs, pay and conditions.

The union said rail staff who worked through the COVID pandemic were facing pay freezes and hundreds of job cuts.

Members voted overwhelmingly for industrial action last month.

The RMT's general secretary Mick Lynch said: "Our union will now embark on a sustained campaign of industrial action which will shut down the railway system.

"Rail companies are making at least £500m a year in profits, whilst fat-cat rail bosses have been paid millions during the COVID-19 pandemic.

"This unfairness is fuelling our members' anger and their determination to win a fair settlement."

He added: "It has to be restated that the source of these disputes is the decision by the Tory government to cut £4bn of funding from our transport systems – £2bn from national rail and £2bn from Transport for London.

"As a result of this transport austerity imposed by the government, the employing companies have taken decisions to savage the Railway Pension Scheme and the Transport for London scheme, cutting benefits, making staff work longer, and poorer in retirement, while paying increased contributions."

Which train lines will be affected?

RMT members at the following 13 train companies will take part in the strike:

• Avanti West Coast

• c2c

• Chiltern Railways

• Cross Country Trains

• East Midlands Railway

• Great Western Railway

• Greater Anglia

• LNER

• Northern Trains

• South Eastern Railway

• South Western Railway

• TransPennine Express

• West Midlands Trains

Can you get a refund for delayed or cancelled trains?

Getting a refund is straightforward using the Delay Repay scheme, which sets out a minimum rail companies must meet.

Passengers are refunded depending on the length of delay, ticket type and rail firm they are travelling with.

They are required to give refunds for delays over 15 minutes, with compensation ranging from 12.5% to 100% of the full ticket price.

Passengers can send claims to the relevant train firm online or through the post.

The money is then paid to your account within two weeks.

Rory Boland, editor of Which? Travel, said: "With the upcoming train strikes fast approaching, many people will be wondering what to do if they bought a ticket and have now had their train cancelled.

"If you can't travel and you have an unused ticket, you should be able to cancel and get a fee-free refund.

"A full refund also applies if you have started your journey but are unable to complete it due to delay or cancellations, and so have returned to your departure point."

How has the government responded?

Transport secretary Grant Shapps called the strikes "entirely pointless" and "counterproductive".

He said: "These discussions were under way when suddenly the union decided it would ballot its members, telling them, incorrectly, that it was to get them off a pay freeze.

"The pay freeze, which was across all of the public sector, nearly every part experienced a pay freeze, was in any case coming to an end."

A Department for Transport spokesperson added: "Strikes should always be the last resort, not the first, so it is hugely disappointing and premature that the RMT is going ahead with industrial action."

Meanwhile, Network Rail chief executive Andrew Haines said the strikes have been timed to cause "maximum disruption".

Rail Delivery Group chairman Steve Montgomery called the strikes "needless and damaging".