Survey work begins next week to inform the design of the long-term solution for the A83 at the Rest and Be Thankful.
Transport Scotland said topographical surveys, including the use of a drone, are to start on Monday (13 November), subject to weather conditions.
The route is frequently blocked by landslides, despite repeated and ongoing works to protect it, and the Scottish Government has said it is pursuing a two-phased approach with shorter-term investment in the existing route in tandem with work to identify a permanent solution.
In March 2021 it identified the Glen Croe corridor, adjacent to the existing road, as its preferred route for the long-term solution.
A Transport Scotland spokesperson said: The surveys are aimed at capturing features such as roads, service covers, structures, vegetation and boundary lines along the preferred route corridor.
‘We apologise for any inconvenience these works may cause and would thank road users and local people in advance for their patience during the works. The contractor will closely monitor the operation of the traffic management measures to ensure that any delays are kept to a minimum.’
The work is expected to last around three weeks, taking place Monday to Friday with no work at weekends.
Transport Scotland said some traffic management measures will be required on the A83 and the B828 to allow the work to be carried out safely. These will include rolling lane closures with two-way traffic lights, moving as the survey work progresses.
