Two lanes are currently closed on the M25 causing chaos for those travelling over the Easter Bank Holiday weekend.
Delays of over 40 minutes are expected for motorists on top of usual travel times.
National Highways said: "Lanes 2 and 3 (of 3) are currently closed on the #M25 clockwise within J23 South Mimms due to a collision.
At J22 near St Albans there is severe congestion.
"Normal traffic conditions are expected between 11:30 and 11:45."
For the most up-to-date information about the county's roads, visit our LIVE Hertfordshire traffic map.
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Do you have a live or breaking news story from across Hertfordshire? Email: hertslivenews@archant.co.uk
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