The historic first section of dual-carriageway, built as part of the multi-billion-pound A9 dualling programme, has been opened to traffic.
Restrictions were lifted in the early hours of Saturday morning to allow vehicles onto the new four-and-a-half mile section between Kincraig and Dalraddy.
The 40mph speed limit was also removed along the £35 million stretch.
Transport Scotland said the upgrade will lead to safer overtaking opportunities, reduced frustration, shorter journey times, less congestion and a better all-round experience travelling on the A9.
Opening the road also splits up what has been the largest section of single carriageway between Perth and Inverness.
The Cabinet Secretary for Economy, Jobs and Fair Work, Keith Brown, said: “Drivers will welcome having access to an additional section of dual-carriageway which is the first of many to come as part of the A9 Dualling Programme.
“We expect to be awarding the contract for the Luncarty to Pass of Birnam section in the first half of 2018 as we press on with our programme to build a fully dualled A9 between Perth and Inverness.
“This project will open up our country for trade and tourism, delivering significant economic benefits.”
As is usual for projects of this size and type, the contractor will remain on site for some time after the main traffic management is removed in order to undertake necessary finishing, snagging and landscaping works.
The Kincraig to Dalraddy route was built as part of a joint venture by Wills Bros Civil Engineering and John Paul Construction.
The £3 billion dualling scheme, which involves upgrading more than 80 miles of road, is on target to finish in 2025.
