Buses will replace trains between Bury St Edmunds and Cambridge on the weekend of the town’s popular Christmas Fayre.
Network Rail says it is installing a new track as part of its Railway Upgrade Plan to deliver more reliable services for passengers.
But the timing of the works has been criticised, with around 120,000 people expected to visit Bury over the course of the fayre, which will run from November 26-29.
County and borough councillor David Nettleton said: “They must have to reschedule they’re engineering works. Because of pressures brought on by the fayre we need as many transport options as possible. They’re just not thinking about the needs of the town.
“Why wouldn’t they want to change it, surely they’ve got some flexibility?”
Mark Cordell, chief executive of Ourburystedmunds, said: “I hope this wont detrimentally effect the number of people who visit the Christmas Fayre.”
A spokeswoman for St Edmundsbury Borough Council said: “Traffic management is at the heart of a successful Christmas Fayre and we have robust plans and lay on extra parking capacity to welcome visitors.
“While it is disappointing that anyone coming from the Cambridge direction will be unable to do so by train, the bus replacement service will bring them direct to the rail station.
“If they choose to come by car, they will find the 1,000 space A14 Park and Ride directly on route. This year we are offering incentives to people to cycle to the fayre as well as encouraging as many who are able to enjoy the walk from park and ride sites.
“We will be keeping everyone updated on travel conditions over the weekend, so they can enjoy themselves to their fullest.”
A spokeswoman for train operator Abellio Greater Anglia said: “We will do everything we can to provide a reliable rail replacement service while Network Rail carry out work to improve the track on November 28/29. Information for passengers is available on our website and we would like to apologise for any inconvenience caused.”
There will be further alterations to train services from November 30 to December 2 with Bury and Stowmarket among stations affected.
For travel information and revised timetables, visit www.abelliogreateranglia.co.uk