Commuters in Milngavie and Bearsden were left with no train services following emergency engineering works.
A small stretch of ‘defective railway’ was uncovered near to Glasgow Central early on Tuesday morning, prompting urgent repairs from Network Rail workers.
Engineers were on site from 6.30am, working to replace the affected section of track.
The works caused dozens of delays and cancellations as thousands of commuters struggled to get to their destinations.
A spokesperson from track operator Network Rail said a number of early-morning services were affected by the repairs.
He said: “A section of track near to Finnieston was identified as being defective, which happens as a result of general use.
“The average piece of rail has the life span of around 20 or 30 years and needs to be replaced.
“We have been able to allow some trains through but instead of the usual 50-60mph they have had to pass at walking pace.
“Obviously, this has caused some serious disruption, especially considering the volume of early-morning services heading from Milngavie into Glasgow and to Edinburgh.”
Elsewhere, there were additional delays due to signalling problems in the Uddingston area.
As a result, a number of Milngavie to Motherwell and Milngavie to Edinburgh trains were severely delayed or cancelled, with a number of other services terminating before their destination.
ScotRail said there were a number of ‘knock-on’ delays as a result and offered the use of some First bus services as an alternative.
A spokeswoman said: “We apologise for any inconvenience caused by circumstances beyond our control.”