The Mountain Road will be closed for around five weeks between the Creg ny Baa and Brandywell Corner from mid-September.
It’s to allow for construction works to take place - with Infrastructure Minister Michelle Haywood saying it will improve a section of road which has seen five crashes in the past three years.
Work will include channels to help manage water on the road and reduce the risk from ice in winter.
Originally scheduled for spring before a breakdown at the government asphalt plant, work will now start from Monday, September 15.
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