Construction on the West Coast Main Line will cause severe disruption to rail travelers during the Easter weekend.
Shawfield Junction, south of Glasgow, is undergoing a £ 4 million signal and track upgrade, which will be completed on Tuesday morning.
Passengers traveling between Scotland and the north of England are affected.
Network Rail admitted that the work would lead to disruptions, but said that a short-term disruption to the line was inevitable.
National Rail said travel times to and from Scotland could be significantly extended over the holiday weekend.
There are no trains north of Lancaster. This means that rail vehicles between Glasgow and the north of England operate on Saturday, Sunday and Monday.
In addition, the closure of London Euston Station means that passengers need to change service to reach the English capital.
Virgin Trains has advised passengers to avoid traveling.
Donald Morris, Program Manager for Network Rail Infrastructure Projects, said, "Our engineers will work hard to complete this complex program for passengers as quickly as possible.
"The West Coast Main Line plays an important role in the country's economic life – transporting passengers and cargo – and this work will help to improve reliability.
"We understand the inconvenience that this work can cause some passengers and residents, but such a huge investment in the railroad is not possible without short-term closure of the line."
Further south of the West Coast Main Line, engineers will also work between Beattock and Abington in South Lanarkshire.