Rail services across large parts of the country face disruption because of strikes. Here is all you need to know.

Which train companies are affected?

Members of the Rail, Maritime and Transport union (RMT) on South Western Railway (SWR) and workers on Arriva Rail North (Northern) are striking on Saturday in a row over the role of guards on trains.

How are Northern services impacted?

Northern has said it will only able to put on a “very limited” service and urged passengers to check if their trains are running “up to the last minute before travelling”. The operator said “very few” trains will be running before 9am and after 6pm, with services down to about 30% during day.

Some routes will have no services at all, with replacement buses laid on, while others will be severely limited and all are expected to be busy with passengers. The network is expected to come under particular pressure around Liverpool, where The Giants festival is due to draw crowds in their thousands.

Northern regional director Liam Sumpter called on customers to plan their journeys carefully. “Those services we are able to run will be extremely busy,” he said.

A map can be viewed at northernrailway.co.uk/strike

How are SWR services impacted?

Most of the network is running a reduced service. SWR said some routes will not have a train service or a replacement bus service. Tickets can be used on additional bus operators outside of London.

Passengers were urged to check southwesternrailway.com for details on how their journey may be affected.

How long are the strikes taking place for?

RMT members who work for SWR are on the second day of a 48-hour strike. It is the seventh 24-hour strike of nine planned for Northern RMT members.

Why are the strikes taking place?

The RMT is locked in a long-running dispute with train companies over plans to remove guards to create driver-only trains.

Why do they object?

The RMT said a survey of 800 guards showed the “vital” safety role they play, backed up by British Transport Police figures showing a 17% surge in violence on Britain’s railways. Four out of five said they had prevented an emergency situation, half had prevented at least one sexual assault and 98% have dealt with anti-social behaviour.

What do MPs say?

Rachael Maskell, shadow transport minister, said the spike in crime “underlines the importance of a properly staffed railway to keep passengers and employees safe”.