A 71-year-old Cumbrian railway bridge is set to be replaced, with site preparations underway.
Network Rail announced the replacement of Clifton bridge, near Penrith, in 2026, as it has reached the end of its life.
The bridge, which carries trains over the M6 between the North of England and Scotland, currently only allows one train on it at a time, causing delays.
As a result of the work, there will be road and rail closures in January 2026.
The old bridge will be dismantled and taken away on the M6, while the new bridge materials will be delivered by road and constructed on-site.
The project team has begun preparations by setting up a compound for the work.
National Highways, on behalf of Network Rail, is building an access road to the work site.
Traffic management will start this month on the M6, approximately three miles south of Junction 40, and will remain until the end of the project in 2026.
Olivia Boland, Network Rail sponsor, said: “We are rebuilding Clifton bridge over the M6 to keep rail passengers and motorway users safe for years to come.
“This project is essential as the bridge has reached the end of its life.
She added: “We’re working with National Highways to make sure we can carry out our work as safely as possible with as little inconvenience to local people and the travelling public.
“Thank you for your patience during this critical work.”
Steve Mason, National Highways’ programme delivery manager, added: “This is an essential Network Rail project to secure the future of one of the most important railway lines in the country.
“We’ll be working closely with Network Rail throughout to keep motorway users and local people up to date with developments – especially as we approach the two weekend closures of the motorway at the beginning of next year.”
The railway is set to be closed for two weeks in January 2026 to allow for the demolition and replacement of the bridge over two weekends.
Network Rail is working with train operators to plan alternative transport options during this time.
The M6 will also be closed over two weekends in January 2026.
It will be closed in both directions from the evening of Friday, January 2, to the morning of Monday, January 5, and from the evening of Friday, January 9, to the morning of Monday, January 12.
The closures will be between junction 39 at Shap and junction 40 near Penrith.
Network Rail and National Highways are yet to release plans about diversionary routes.