Commuters have been reminded that a section of the Glasgow-Edinburgh mainline will close for 44 days this summer.
The Winchburgh tunnel in West Lothian will be closed from June 13-July 27 to allow installation of power lines as part of a £750 million improvement programme that will deliver faster trains.
Services from Falkirk High and Polmont stations to Edinburgh will be diverted via Dalmeny, near South Queensferry, as a result.
This could mean journey times increase by around 20 minutes and the number of trains stopping at Falkirk stations could be reduced.
As part of the 44-day project, engineers will be lowering and relaying the two lines of track through the 330m tunnel and installing equipment to carry the overhead power lines needed for the electrification of the railway.
The tunnel will need to remain closed while engineers work 24-hours a day to deliver the work as quickly and safely as possible.
Network Rail, Transport Scotland and ScotRail said they were working closely to ensure that a temporary timetable is in place to minimise disruption and provide alternative travel options for passengers.
More information can be found at www.scotrail.co.uk/winchburgh and passengers are urged to allow more time for their normal journey, to plan ahead and to check before travelling.
Passengers are also being advised of the changes through leaflets and posters at stations along the line of the route.