The Mountain Road will close for 6 weeks from 28 February.
It's as work gets underway in preparation for this year's TT.
The closure was supposed to take place last August but was pushed back until 2022 following consultation with both stakeholders and the public.
Ramsey to the Bungalow will be shut until March 28, followed by the entire mountain route for a further three weeks - closures are thought to be lifted by April 15 at the latest.
Snaefell and the Victory Café will be accessible for the duration of the works, as will the Creg-Ny-Baa.
Meanwhile, The DOI has confirmed the road will be accessible between the Bungalow and Creg-ny-Baa at peak times.
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