A key part of the project to dual the entire A11 road between Norwich and London is set to open on Monday 28 April.
For the first time, the bypass around the village Elveden in Suffolk to south of Thetford, will be open to traffic.
The Highways Agency says: "The new bypass will run with one lane open in each direction, and with a 40mph speed limit, between Chalk Hall Farm to near the end of the scheme, just before Thetford roundabout."
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