The A66 is closed in both directions between Scotch Corner and the A685 at Brough due to heavy snow fall overnight.
National Highways said: “We currently do not have an expected re-opening time as snow is forecast to continue to fall until late morning in the area.
“National Highways has winter maintenance teams working to keep the road clear and minimise the length of time the road needs to remain closed.
“However the current weather conditions means the road is currently unsuitable to allow traffic to use.
“Road users should consider using either the A69 or M62 as an alternate trans-Pennine route. As this will add significant mileage to such journeys you should allow plenty of extra time for your journey.”
Drivers are also urged to avoid Honister Pass following a one vehicle collision.
Cumbria police said the incident occured due to weather conditions and the road is blocked.
It added: “The vehicle will be recovered once the weather conditions improve.”
