Rail services connecting north and south Wales could be cancelled for up to a week due to flood damage.
Flash flooding has washed away parts of the track at Pontrilas, Herefordshire, disrupting trains running between Hereford and Abergavenny .
Wales saw torrential rain for most of Saturday with flooding reported across the country.
Some parts saw around 7cm of rainfall on Saturday, with one pub left under seven feet of water, causing thousands of pounds of damage.
Network Rail said the "extreme weather" meant the busy route would be closed for "some time".
A statement said a train driver reported fast flowing water shortly before 1pm on Saturday near Pontrilas. The flash flooding washed away the railway foundation stone leaving parts of the track suspended above the water.
Network Rail engineers have carried out a full assessment of the track to find out how long repairs will take.
A Network Rail spokesperson said: “We understand how disruptive the closure of the Marches line will be to passengers and we’ll work as fast as we can to get it back up and running again. Although we always plan for extreme weather it’s nearly impossible to mitigate such heavy rainfall of the like we’ve seen over the last 24 hours.
"We thank passengers for their patience while we make our repairs and advise them to check National Rail Enquiries to find alternative routes while the Marches line remains closed.”
A view of the flooding that affected Wales yesterday:
Transport for Wales said all lines were closed between Hereford and Newport.
They added that initial inspections suggested the repairs would take at least seven days to complete.
Replacement bus services between Newport and Hereford will run via Cwmbran and Abergavenny, in both directions, until the end of November 1.
Further updates can be found here .
