Work to begin on A55 Pen-y-Clip and Conwy tunnels
Improvement work to tunnels on the A55 road in Conwy county is due to begin on Sunday.
The Pen-y-Clip tunnel near Penmaenmawr will shut for two weeks, with traffic diverted around the headland.
The Conwy tunnel will be reduced to one lane for three weeks from 14 February.
There will be some short-term closures but Transport Minister Edwina Hart said officials would do "all they can" to keep disruption to a minimum, and the work would be completed by early March.
Plaid Cymru AM Llyr Gruffydd said: "The works that will be carried out on the tunnels must not over-run as users will face weeks of traffic chaos due to these tunnel closures."