Travellers using Edinburgh Airport face major disruption following a decision to close the Forth Road Bridge until the new year.
Transport minister Derek Mackay said structural faults would take at least three weeks to repair and safety was ‘paramount’.
He said a contingency plan was being drawn up, including extra trains and buses and possibly a ferry.
But Edinburgh Airport is advising passengers that alternative routes will add at least one hour on to their journeys.
"Drivers will need to use the Kincardine or Clackmannanshire bridges," it said. "However, this will add at least an hour to journey times – with this likely to even greater due to congestion."
It advised passengers to add a nearby hotel room to your airport parking ‘for just a few pounds extra’ and ‘take away the anxiety of getting to the terminal on time’.
Gordon Robertson, Edinburgh Airport communications director, said: "We have alerted passengers via social media about the Forth Road Bridge closure and are requesting people plan alternate routes from the north and factor in extra time for their journey to the airport . Passengers travelling from the west should also be aware of potential traffic delays as a result of the closure."
Inspections last week found a 20mm-wide crack in a truss under the southbound carriageway close to the bridge’s north tower.
The 51-year-old bridge is due to be replaced by a new crossing in about 12 months.
Emergency service vehicles will still be able to use the bridge when responding to calls.
"We are aware of the potential economic impact, for strategic traffic in the east of Scotland and on people living in local communities," said Mackay.
"This is an unprecedented challenge in the maintenance of the Forth Road Bridge. On balance following advice from engineers and independent experts, the full closure is essential for the safety of the travelling public and to prevent further damage to the structure of the bridge."
Repair work is weather dependent and would be followed by a further week of tests and inspections, he added.
