More trains will be laid on between the Cynon Valley and Cardiff this Christmas.
Arriva Trains says it is introducing the extra Sunday trains this December as a pilot study.
The four additional services will include an 08:54 from Aberdare, meaning customers can travel by train into Cardiff before 10am for the first time.
They will be in place for the 3rd, 10th and 17th of December initially to assess the demand for them.
If demand will proves sufficient the extra services will be made permanent.
The additional services mean there will be hourly services to Cardiff until 12:53 every Sunday and hourly services back from 15:41 to 19:41.
Arriva Trains Wales have been working with local AM Vikki Howells, who conducted a survey showing 95 per cent of people in the area said they would like a more regular Sunday service.