The A140 is now clear after a crash which caused delays on Sunday afternoon.
Drivers were advised to avoid the road if possible after a crash which saw Norfolk Police called on the scene close to Dunston Hall, south of Norwich.
"There is considerable traffic build-up," the force said in a post on social media.
The post added: "Drive safe and seek alternative routes where possible."
Drivers were advised to avoid the A140 if travelling between Norwich and Long Stratton.
But the A11 should not be used beyond Attleborough, as that too was closed for roadworks.
• For up-to-date information about the county's roads, visit our LIVE Norfolk traffic map.
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