Network Rail is upgrading tracks through the 180-year-old Summit tunnel between Rochdale and Hebden Bridge. It was built between 1838 and 1841 as part of the Manchester and Leeds railway.
The £2m Great North Rail Project investment by Network Rail will take place between 23 and 31 October.
For the work to take place the railway will be closed for nine days.
Karen Hornby, Network Rail’s North West head of performance and customer relationship, said: “We appreciate passengers’ patience while we carry out these vital improvements to Summit tunnel as part of the Great North Rail Project. The work will mean fewer train delays on the Calder valley line and make tracks inside the Victorian-built structure fit for the 21st century.
“However, replacing track like this means we have no choice but to close the line for old sections to be ripped up and replaced with new. I’d urge anyone planning to travel over the nine-day railway closure to check National Rail Enquiries to they know exactly what to expect from their journeys.”
From October 23 to October 31 rail replacement buses will be in operation to keep passengers on the move between Rochdale and Hebden Bridge.
At weekends buses will also replace trains between Manchester and Rochdale as well as between Hebden Bridge, Burnley Manchester Road and Accrington stations.
Network Rail is also working in partnership with the Environment Agency which will be upgrading a culvert beneath the railway lines as part of a wider flood defence project in the area.
Nick Pearson, senior flood risk advisor with the Environment Agency, said: “Working in partnership with Network Rail as part of the proposed £56m Rochdale and Littleborough Flood Risk Management Scheme will make a huge difference to rail passengers, residents and the local economy.
“This project, one of the biggest flood alleviation schemes in the north of England, will play a crucial role in better protecting the community from the risk of flooding and we are pleased to see it progress.”