Work starts on A96 Inverness-Nairn dualling project
Work has begun on a 20-week project examining ground conditions along the proposed route of dual carriageway between Inverness and Nairn.
Transport Scotland said six out of 650 locations to be investigated would require traffic management measures.
A £50m contract to design dual carriageway from near Nairn to Fochabers could also be awarded this spring.
It is planned to eventually dual the entire length of the A96 by 2030.
The trunk road, most of which is single carriageway, links Inverness and Aberdeen.
Keith Brown, secretary for infrastructure, investment and cities, said: "The work on this road scheme is moving apace with draft orders expected to be published later this year."
He said the ground investigation work was necessary ahead of construction of the new road in the future.
Mr Brown added: "Hand in hand with this scheme, we are taking forward our plans for the 29 mile western section between Hardmuir and Fochabers with four well respected engineering consultancies or joint ventures in the running for the £50 million design contract.
"We hope to award this contract later this spring."