Train commuters are facing three months of delays as work to dual the Aberdeen to Dyce gets under way.
The line is expected to be largely out of operation until August 20, and ScotRail Alliance is urging passengers to seek alternative forms of transport.
That will include public transport, including improved bus links, and the operator has pledged to look at providing additional services if demand requires.
It has also suggested that commuters temporarily swap rail travel for bicycle, with the national Cycle Route 1 running between Dyce and the heart of Aberdeen.
ScotRail Alliance notes the cycle journey – an “ideal way” to get to the city centre – would take around 35 minutes, though it would also mean negotiating the Haudagain roundabout.
The operation began at the weekend, with a two-day closure of the line to allow preparatory work and a bridge demolition to be carried out.
From Saturday, the line will close for 14 weeks and is not expected to reopen until August 20.
Head of Aberdeenshire Council’s infrastructure services committee, Peter Argyle, said he expected there would be “some disruption” but that it would be worth it for a “much improved service”.
He said: “The net result will be such an improvement that it is worth going through this pain.”
The temporary closure will allow engineers to double the track in between Aberdeen and Dyce and is part of the multi-million-pound Aberdeen to Inverness Improvement Project.
A similar closure will take place in May 2019, between Dyce and Inverurie, to allow for that section of track to be doubled and for the station to be reinstated at Kintore.
Buses will replace trains between Aberdeen and Dyce during the upgrade work and ScotRail has published specific journey information on its website.
The information includes bus timetable information, as well as alternative travel options such as cycling and details of other commercial bus operators.
Rail users have expressed some cynicism at the arrangements.
One Dyce resident, Kelly-Anne Martin, 47, said she had “struggled” to find the information on the Scotrail website and that when she did she found the offerings “inadequate”.
She said: “They are putting on buses every 30 minutes in the morning, but I had thought they would have had more than that.
“I can’t see that there will be enough for everyone to get into Aberdeen for 9am; especially as so many people come in from further up the line in Inverurie too.”
ScotRail Alliance’s Graham Heald accepted there would be inconvenience and delays but said efforts had been made to provide as much information about alternative transport as possible.
“We know lengthy line closures can be a real inconvenience for customers and we’re doing everything we can to keep people moving during the work,” he said.
“We’ve published travel information on our website and would encourage customers to plan ahead, considering their travel options and remember that journey times will be longer than normal.”
ScotRail has confirmed it will monitor passenger numbers and customer feedback over the coming weeks and will review its replacement bus plans if needed.