Local train services will be affected by engineering works over the Christmas and New Year holidays.
Network Rail will be carrying out essential works to the west of Cardiff Central station from Christmas Eve until New Year's Eve.
Transport for Wales (TfW) says some services may be retimed and subject to platform changes.
There'll be no trains on Christmas Day and Boxing Day with services finishing early on Christmas Eve and starting later next Saturday (27th December). There'll also be an early finish on New Year's Eve.
On New Year's Day, there'll be a reduced hourly service on the Vale of Glamorgan line via Barry - and no services to and from Penarth and Cardiff Bay. Trains will also not call at Barry Island but a full service will run on the South Wales mainline.
Marie Daly, TfW's chief operating officer, said: "With essential engineering work taking place, planning ahead has never been more important."
"Our dedicated teams will be working throughout the festive season to keep services running across the Wales & Borders network and get passengers safely to their destinations."
All services to and from the west of Cardiff Central will call at all stations where possible and divert via Ninian Park.

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