Train services on the Vale of Glamorgan Line are being disrupted by major engineering works this week.
Network Rail says all journeys between Cardiff Central and Penarth, Barry Island and Bridgend (via Barry) will be affected between Saturday 29th March and Friday 4th April.
Replacement bus services are running throughout the week.
The essential work will see 12 engineering trains being used to install new rail tracks and to replace sleepers and points.
Teams will also be working on vegetation management, examining structures along the track such as bridges and retaining walls, as well as removing grafitti and litter in various locations.
Network Rail says the works will be completely "as efficiently and safely as possible" with disruption being kept to a minimum for passengers and nearby residents.
Nick Millington, Wales and Borders route director at Network Rail, said: "We are working really hard to improve train service punctuality and this essential work is a part of our commitment to do that."
“We recognise there is never a good time to close the railway, but we have planned the renewals to minimise disruption as much as possible."
“I would like to thank passengers for their patience and urge them to check their journeys before travelling.”

Penarth: new bid to turn former gym into shop
A New Brewery is coming to the Vale of Glamorgan - Nash Point Brewing Co in Barry
Ex-shooter hits Postcode Lottery jackpot
Cogan: police investigate teenager's death
Convertible firearms targeted in gun amnesty
No Aqua Park at Cosmeston this summer - Council
Councillors back call for quieter fireworks
Six Nations kick off for DES scheme
Headteacher up for St David's Award
25 arrested in second day-of-action
South Wales Police precept set to rise
Drug dealer jailed after high-speed chase
April rollout for soft plastics recycling
More support for people affected by ketamine
Two men charged with tool theft
Councillors back Old Harbour reserve calls
Missing person rescued near Rhoose Point
More support for farmers to join subsidy scheme