THE A59 at Kex Gill between Harrogate and Skipton remains closed for safety reasons.
North Yorkshire County Council shut it last night after significant movement was identified in the hillside, resulting in substantial cracks on the slope.
The council has been constantly monitoring and measuring the hillside following recent heavy rains.
Today, a county council geotechnical engineer carried out a detailed inspection of the ground and the road will remain closed until the results of the survey have been carefully examined.
This stretch of road runs across very high ground between even higher moorland between Skipton and Harrogate and has in the past been affected by landslips in bad weather.
In 2011 the county council undertook to strengthen the banks and resurface part of the road during a five-week road closure.
Two years ago the council undertook some additional drainage measures on the slope in a bid to improve stability and has continued to keep a close watch of the area.
County Councillor Don Mackenzie, North Yorkshire’s executive member for highways, said: “We apologise for any inconvenience that this may cause to road users. However, safety on the highway must be our greatest priority. We constantly monitor this area and in the past have undertaken major works to stabilise this slope. It now needs urgent and detailed investigation by our expert engineers.
“As part of our strategic transport plan we have put forward proposals for a major realignment at Kex Gill in order to create an A59 route on the other side of the slope.”

Skipton MP Julian Smith said he supported North Yorkshire County Council in its decision.
"I was concerned to see that the A59 at Kex Gill between Harrogate and Skipton has been closed due to significant movement of the bank above the road," he said.
"North Yorkshire County Council moved very quickly and closed the road this afternoon. Drivers should be aware that the closure has led to a significant diversion. I will continue to monitor the situation on the A59 and support the council."
He added: "I understand that the closure may prove to be a considerable inconvenience to many people, however, ensuring the safety of all road users is a matter of absolute priority and I support the council in their decision."
A diversion route has been put in place and is signposted between Skipton and Harrogate.