The Mountain Road will remain closed from Ramsey to the Bungalow until Tuesday.
The Department of Infrastructure says the route will re-open then at the earliest.
It's due to the high risk of further land slips, following one yesterday caused by the weather.
Work is currently underway to try and stabilise the area.
Weather warning for snow tonight
MHK queries safety at primary school in Ballabeg
Gales put two ferry sailings at risk tonight
Should the Island throw a birthday party for Barry Gibb?
Warning issued over icy roads
High ground could see 4 inches of snow on Saturday night
Mountain Road unlikely to open before Monday
Yellow warning for freezing temperatures tonight