The newly upgraded A11 between Thetford and Fiveways roundabout has been formally opened by transport secretary Patrick McLoughlin.
The work involved widening 5.5 miles of the road, which amounts to nine miles of new lanes. The project was also responsible for building a 3.6 bypass for the village of Elvenden. This included an underpass by the war memorial, thanks to additional funding from Suffolk County Council.
The Highways Agency project cost £105 million, and was part of a £3.3 billion programme of road investments approved by the government at the last spending review. Work began in January 2013.
It is expected to improve congestion and road safety in the area, as it is a major link between Norwich and the M11.
At the official opening, Mr McLoughlin hailed the completion of the project. He said: “It will not only benefit those who use the road every day but create jobs and opportunities, benefiting hardworking families across the east of England.”