Motorists are being warned there will be six months of delays in the west of the Isle of Man from this morning (Monday).
The A3 is being resurfaced in Foxdale and drainage work will be taking place between Brookfield Bank House and the Ballanass Road junction.
The reconstruction work is expected to take about 25 weeks.
Infrastructure chiefs are thanking motorists and pedestrians for their patience, in advance.
There will be 24-hour traffic lights in operation for most of the time, but there will also be a complete closure for two weeks from February 20, to allow for extensive drainage work.