Train strikes: GWR maps show which rail lines and services are operating this week

Great Western Railway has issued maps to illustrate the scale of the disruption facing travellers during this week's train strikes. The rail operator is one of many nationwide having to cancel hundreds of services and heavily reduce more during three strikes this week - today, Thursday and Saturday.

Industrial action has been called by transport union RMT in response to what it says is an 'aggressive agenda of cuts to jobs, conditions, pay and pensions'. The three walkouts this week could be followed by more if no agreement is reached, with train users across the country warned not to travel unless absolutely necessary.

GWR is running 'very limited services' from Bristol Temple Meads on the strike days, and reduced services on the days in between. Even on non-strike days, no trains are running before 7am.

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The two maps show which lines are open on the different days, in green, and closed, in red.

GWR services on strike days - June 21, 23, 25

The services running, and not, during the strike action on June 21, 23 and 25 (GWR)

GWR services on non-strike days - June 22, 24

The GWR services operation on June 22 and 24, when there is no strike action (GWR)

A GWR statement said: "Only travel by rail if necessary. If you do travel, expect severe disruption and plan ahead. Services will start later and finish earlier throughout the strike period.

"On strike days, an extremely limited service will operate between 07:30 and 18:30. On non-strike days, no services will run before 07:00. GWR will operate as many trains as possible during the strike action however, most train services will be affected on the days announced. Due to the timing of the strike action, services in between strike days will also be affected.

"Where we are able to run services, they are expected to be extremely busy. We are not able to provide bus replacement services."

No GWR rail services will be able to operate on strike days on the following routes:

• all lines in Cornwall, including all branch lines
• all branch lines in Devon (Barnstaple, Exmouth, Paignton, Okehampton)
• South Wales main line (Carmarthen/Swansea – Cardiff Central)
• Heart of Wessex line (Castle Cary – Weymouth)
• Severn Beach line (Bristol Temple Meads – Severn Beach)
• North Cotswolds line (Hereford/Worcester – Oxford)
• South Cotswolds line (Cheltenham – Swindon)
• Worcester/Gloucester – Bristol
• Kennet Valley (Reading – Pewsey)
• North Downs line (Reading – Gatwick Airport)
• South Coast (Westbury – Southampton/Portsmouth Harbour)
• Greenford branch line (Saturday 25 June only)