Following a multi-car collision earlier today (March 18) on the M25 there are 'severe' two hour delays for motorists.
National Highways closed two lanes earlier but have since re-opened all the lanes clockwise between junction 24 at Potters Bar, Barnet and junction 25 Cheshunt and Enfield.
National Highways said: "There are severe delays of at least 2 hours above usual journey times between J21a and J25."
Motorists have been advised to seek alternative routes where possible.
For the most up-to-date information about the county's roads, visit our LIVE Hertfordshire traffic map.
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