Motorists are being asked to plan ahead as preparatory work starts on a “challenging” section of the A9.
Ground investigation work will begin on Monday, February 13, between the Slochd and Dalraddy.
The work is expected to take seven weeks.
The 15 mile stretch is seen as one of the most technically challenging in the entire A9 dualling project.
The road is tightly lined at Slochd with rockfaces and the Highland Mainline railway.
Major junctions are also needed to provide access to the villages of Carrbridge and Aviemore.
Most of the work will be carried out off the existing road – but traffic management will be in place to allow work beside the carriageway to take place.
Traffic management will include short, alternate single file traffic sections controlled by temporary traffic lights.
A Transport Scotland spokesman said: “This ground investigation is needed to get vital information on the existing ground conditions in the vicinity of the A9 carriageway between Dalraddy and Slochd as we progress our plans to dual the road. This is the latest in a series of ground investigations taking place along the route.
“We apologise for any inconvenience these works will cause and would thank road users and local communities in advance for their patience over the next few weeks.
“The contractor will closely monitor the operation of the traffic management measures to ensure that delays are kept to a minimum.
“When planning their journeys, we’d encourage drivers to visit the Traffic Scotland website for the latest travel updates.”