The road upgrades on the A1 at Harrogate and Knaresborough are set to be complete in the next few weeks.
The £10m National Highways project aims to ease congestion by widening lanes on three of the four slip roads near Junction 47 of the A1.
North Yorkshire County Council says the work is expected to be completed by the end of March.
Don Mackenzie, the council's executive member for access, said: “The finish line is in sight for this important scheme which will support the future growth of the Harrogate and Knaresborough areas."
What are the changes?
The scheme has involved the widening of three of the four slip roads onto and off the roundabout to increase capacity, as well as a number of junction improvements.
Traffic signals have also been installed on the roundabout to improve traffic flow, and added to the T-junction between the A168 and the A59 a short distance from Junction 47 on the York side to benefit drivers turning onto the A59 and to improve safety.
To the west of Junction 47, between the A1 and the Flaxby roundabout, a lane has been added for traffic travelling east, so there will be two lanes in each direction between those two roundabouts.
Final repair works on the A168 bridge, and verges along with resurfacing of the A59, will run from 14 March to 26 March - with overnight weekday closures.
There could be delays during March and April, once traffic signals are installed, whilst signal timings are adjusted by engineers to the optimum settings for the traffic flow conditions.
Ainsty Councillor Andy Paraskos said: “The upcoming works will involve repairs, resurfacing as well as the installation of road markings and traffic loops.
"For the safety of our workforce this must be carried out under a full road closure and we apologise in advance for any inconvenience this essential work may cause.
“As the end of the scheme approaches we can now look forward to the long-term benefits for residents, commuters and visitors alike.”