Rail strikes next week will see parts of the North West with no passenger services.
Network Rail say there will be no passenger trains running in and out of Chester and Blackpool if the strike goes ahead.
Half of Britain's rail lines will be closed, it said, as strikes happen Tuesday 21, Thursday 23 and Saturday 25 June.
Train operator Northern urged passengers "not to travel" between Tuesday and Sunday.
TransPennine Express told passengers they should "only travel if journeys are essential" on strike days, adding that "services will also be affected on the days following the industrial action, particularly in the mornings".
Tim Shoveller, Network Rail's managing director for the North West and Central region, said: "The service that we can offer to passengers in the mornings is going to be very limited.
"Even on the intermediate days we won't be able to operate anything like a full service with the normal amount of capacity or frequency of trains.
"That's what gives rise to effectively six days of disruption."
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.
Passengers "who must travel" are urged to "plan ahead" to ensure they can complete their journeys within this window, Network Rail said.
Open lines include the West Coast Main Line from London to Scotland via locations such as Preston and Manchester.
Members of the Rail, Maritime and Transport union at Network Rail and 13 train operators are involved in similar disputes over pay, jobs and pensions.
The union has called for a meeting with the government ahead of the action.
Steve Montgomery, who chairs industry body the Rail Delivery Group, said: "These strikes will affect the millions of people who use the train each day, including key workers, students with exams, those who cannot work from home, holidaymakers and those attending important business and leisure events."
Only around 12,000-14,000 services will be able to run on the days following the strikes.
This is because signallers and control staff will not work overnight shifts that begin on the strike dates.
That means trains will not be able to leave depots for up to four hours later than normal.