Train services to and from Barry Island and Penarth have resumed following three days of disruption.
But Network Rail says disruption due to urgent bridge repairs in Cardiff is set to continue into next week.
Services have been suspended since Easter Sunday when work began on a structrual defect between Cardiff Central and Cardiff Queen Street stations following an inspection.
Transport for Wales (TFW) services on the Core Valley lines were affected along with Great Western Railway and CrossCountry trains on the mainline between Cardiff and Newport.
A TFW spokesperson told Bro Radio News that an hourly service is being run to and from Penarth but services to Barry have resumed as normal.
They added: "We'd encourage all passengers to check for the latest information using our website or social media."
Earlier, the rail operator said extensive repairs had enabled mainline services to largely reopen, except for local services to Ebbw Vale, which will run only between the town and Newport for the rest of the week, with connections at Newport for the Welsh capital.
TFW added changes to services were expected until Sunday with replacement buses in place between Caerphilly and Cardiff along with some services on the Coryton line, while other services are being diverted via the City line.
Additional train services are due to be restored in the coming days.

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