Network Rail will be delivering a multi-million-pound programme of maintenance and renewal work on the West Coast Mainline over 10 weekends between April and June this year.
Engineers will refurbish or renew more than 17 kilometres of track at 20 locations along the line between Carstairs and the border.
A bridge near Beattock will also be replaced, drainage systems beneath the line renewed and embankments strengthened as part of the programme.
Due to the complexity of the engineering work and the heavy machinery involved, this investment in the line cannot be delivered without some short-term closures of the railway.
Buses will replace trains between Carlisle and both Glasgow and Edinburgh on weekends between Saturday, April 4, and Sunday, June 7.
On most weekends, the closures will affect services from mid-morning on Saturdays until start of service on the following Monday.
Over Easter and some weekends in May the closures will extend for longer, with buses replacing trains on Monday April 13 and Mondays May 4 and 25.
Lindsay Saddler, head of maintenance for Network Rail Scotland, said: “The work we are undertaking is vital for the long-term future reliability of the line.
“Our engineers will be working around-the-clock to complete these complex projects as quickly as possible.
“We understand the inconvenience these works will cause to some passengers, but working at weekends, when fewer people are travelling, helps us to limit disruption as much as we can.”
Passengers planning to travel on these weekends are advised to check their journey in advance at www.nationalrail.co.uk.