Drivers were today warned of major delays around Glasgow after a weekend closure of a stretch of the M74 was confirmed by Transport Scotland.
The motorway will shut from 18-21 November between junctions four and five for the demolition of a bridge, as The Scotsman revealed two weeks ago.
Delays of more than one hour are expected, and the main diversion route could bring the A8 between Edinburgh and Glasgow to a standstill.
The Scottish Government agency said it would cause the greatest disruption so far as part of the £500 million upgrade of the M74, M73 and A8/M8.
The three-mile section is one of the busiest in Scotland, and used by 70,000 vehicles a day at weekends.
It is also the first closure of its kind for decades.
A Transport Scotland spokeswoman said: “We are warning motorists to expect significant delays on the M74 and surrounding roads as the motorway will be closed from Junction 4 Maryville to Junction 5 Raith for a weekend in November.
“As part of the M8 M73 M74 Motorway Improvements Project, the M74 will be closed to traffic in both directions from 8pm on Friday 18 November to 6am on Monday 21 November 2016.
“We expect queues to be in excess of an hour during the day on the Saturday and Sunday.
“This closure is required to safely demolish Bothwellpark Road Bridge.”
Diversions will be via the A725, A8 and M73, but drivers on these routes are likely to be hit by major delays.
Transport Scotland project manager Graeme Reid said: “This is the most significant road closure we have implemented as part of the works and we are anticipating major delays on all approaches, the surrounding roads and the main diversion route.
“We are advising road users to plan their journey, avoid the area and surrounding local roads, and if possible, to use alternative modes of transport for the weekend.”