Resurfacing work totalling £2.5 million will start this month on the A303 near Amesbury.
The Countess to Solstice Park work along a one mile stretch of the A303 will be carried out over four weekends.
The Solstice Park to Cholderton work along approximately a three and a half mile stretch will be carried out over 25 nights.
Project sponsor Paul Vosper said: “This work will ensure these sections of the A303 remain safe and reliable for drivers for many years to come.
The Countess to Solstice Park resurfacing is scheduled to start on Friday, 30 January and will be completed by 9 March.
The Solstice Park to Cholderton work will start on the night of Monday 2 February and will continue Monday to Friday until 12 March.