Road users in Falkirk and West Lothian are being warned of the emergency closure of the A801 Avon Gorge road from Wednesday 21 March from 6am.
Following the appearance of significant cracks in the carriageway, investigations by Falkirk Council roads teams has found slippage on the adjacent embankment and soft verge causing a potential danger to vehicle users.
The closure will be in place for around 5 weeks as emergency work is carried out to strengthen the verge and to stabilise any further movement.
An 8 mile signposted diversion will be in place throughout the closure.
Councillor Paul Garner, Falkirk Council’s spokesperson for the Environment said: "We do not have any option but to carry out these repairs as a matter of urgency.
"Technical staff have real concerns given the appearance of these cracks and the safety of road users is our top priority here.
"The cracks first appeared on Monday (19 March) and following investigations we are left with no options but to close this strategic route.
"We hope road users understand our reasons for taking this decision and the obvious disruption it will cause however we cannot take any chances with public safety."