Drivers are facing long delays on motorways due to road closures caused by a huge fire in St Albans.
A414 and A4147 near the city are closed as firefighters battle a massive blaze in at a recycling plant in Potters Crouch.
The fire service has said it hopes the busy roads will reopen later this evening or tomorrow.
The closures are causing delays on the M25 and M1.
There is temporary 40mph speed limit on the M1 due to the fire.
The M1 may also be closed if the wind changes and blows smoke in its direction.
Firefighters have been dealing with the fire since Saturday night and say it may take up to a week to put out.