Motorists travelling to Edinburgh on the M90 in Fife are facing a 13-mile-long queue with a 60-minute delay over the Queensferry Crossing.
Reports suggest the backlog has now almost reached the Kelty on-ramp at Junction 4, due to the volume of traffic attempting to drive south to the capital.
No incidents or crashes have been reported on the road, with the delays likely caused due to trains being affected by ScotRail staff taking part in industrial action on Saturday.
Surrounding routes through villages are now also being affected - with queuing traffic reported in Inverkeithing, Rosyth and towards Crossgates.
Earlier on Saturday, Traffic Scotland tweeted: “12:15pm M90 southbound Junction 3-Junction 1A. Traffic very heavy in the area. Approach with care.”
A video posted on Fife Jammer Locations shows the massive queue snaking its way up the M90 at around 2pm.
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